What is synovial sarcoma?

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Synovial sarcoma is a type of soft-tissue sarcoma. It is a rare cancer. Only about 1 to 3 individuals in a million people are diagnosed with this disease each year. It can occur at any age, but it is more common among teenagers and young adults. Synovial sarcoma seems to have a slight preference for males, with 12 male patients for every 10 female patients.

Despite its name, synovial sarcoma is not related to the synovial tissues that are a part of the joints. The disease starts most commonly in the legs or arms, but it can appear in any part of the body. On a pathology report, synovial sarcoma may be classified in different subtypes depending on what it looks like under the microscope or what specific gene mutation is involved. Synovial sarcoma is a high grade tumor. It spreads to distant sites in up to 50% of cases.

What causes synovial sarcoma?

There are no well-established risk factors for synovial sarcoma, but the disease is associated with the chromosomal translocation t(X;18) (p11;q11). This means that parts of chromosome 18 and chromosome X have switched places in synovial sarcoma tumor cells. It is not known whether this mutation occurs randomly or follows a specific chain of events. Because of this translocation, synovial sarcoma cells contain a mutant gene. This mutant gene is thought to contribute to the development of the disease.

What are the symptoms of synovial sarcoma?

Symptoms vary based on tumor location, and the following symptoms may arise:

  • The mass may hinder a bodily function. For example, in the head and neck region, it may cause difficulties swallowing and breathing or it may alter the voice.
  • The mass may be painful, in particular if nerves are involved.

A slow-growing painless mass is common and may give the false impression that it is harmless. When a tumor is painless and deep-seated within the body, it may go unnoticed for a long time. Because tumors can go unnoticed, follow-up guidelines generally involve regular imaging (such as CT scans) after treatment is completed. These tests can detect recurrences at the site of the original tumor or elsewhere in the body. If the cancer occurs elsewhere in the body, it is called metastasis.

Less than 10% of patients have detectable metastases at the time of diagnosis. In such cases, synovial sarcoma tumor cells are believed to have moved from one site (origin) to the second site (metastatic). The lungs are the most common location for metastases.

How is synovial sarcoma diagnosed?

The diagnosis starts with imaging studies. X-ray, sonogram, CT scan, and MRI may be used in the course of evaluating a suspicious mass.

After imaging studies, the next step in diagnosis is a biopsy to remove a sample of the tumor for further analysis. Among the different types of biopsies, open biopsy (a surgical incision is made to remove the sample) or core needle biopsy (a large needle is used to take the sample) are preferred. The use of a fine needle to remove cells can establish the presence of cancer, but often those cells do not provide enough tissue to best characterize synovial sarcoma.

The initial biopsy should be carefully planned by an experienced surgeon or radiologist. That surgeon will take steps to ensure that any tumor cells that are disturbed during the biopsy procedure are completely removed later during surgery to remove the entire mass.

Normally, the sample tissue obtained from the biopsy is sent directly from the procedure room to a pathology laboratory to be sliced and fixed on small glass plates (slides). The pathologist commonly use a technique called immunohistochemistry to learn about the tumor cells. In this technique, the sample tissue is stained with different dyes. How the tumor cells react to the dyes provides additional information about the tumor. Another technique called cytogenetics is often used to detect the chromosomal translocation specific to synovial sarcoma, which helps to confirm the diagnosis.

Once a tumor has been deemed malignant, further imaging studies such as a PET scan of the whole body and/or CT scan of the chest, abdomen or pelvis may be used to look for possible metastases.

Doctors use the material gathered during diagnosis to develop a patient’s treatment plan. During this process, they consider many factors that are specific to the patient, including:

  • the tumor’s size and how invasive it is
  • whether or not there is metastasis at the time of diagnosis
  • whether or not the lymph nodes are involved

How is synovial sarcoma treated?

The primary treatment for synovial sarcoma is surgery to remove the entire tumor with clear margins when possible. "Clear margins" are achieved when healthy tissue surrounding the tumor is removed along with the tumor, making it more likely that all cancer cells have been removed from the area. Depending on the location and size of the mass, it may be difficult for a surgeon to remove adequate margins around the tumor while preserving function. Radiotherapy may also be used, either before or after surgery, to reduce the risk of leaving cells behind.

Chemotherapy (typically Doxorubicin and/or Ifosfamide) might be recommended in the treatment of synovial sarcoma, especially in advanced or metastatic disease. Because synovial sarcoma is rare, there is no consensus among experts on just how much of a role chemotherapy plays in preventing metastases and improving survival. When developing a treatment plan, an oncologist will consider the potential benefits of chemotherapy weighed against the possible negative effects of the treatment. A patient may wish to discuss these issues with the oncologist in order to better understand the treatment plan.

Prognosis for synovial sarcoma patients

Prognosis statistics are based on the study of groups of synovial sarcoma patients. These statistics cannot predict the future of an individual patient, but they can be useful in considering the most appropriate treatment and follow-up for a patient.

Prognosis in synovial sarcoma patients is influenced by the quality of surgery patients receive and the characteristics of the disease (including tumor size, local invasiveness, histological subtype, presence of metastases, and lymph node involvement). Patients with small tumors that can be completely removed with adequate margins at diagnosis have an excellent prognosis. The risk of developing distant metastases is higher for patients with tumors that are larger than 5cm. Patients with the poorly differentiated subtype are considered to have a worse prognosis than those with other subtypes, and patients with metastases that cannot be removed have a poor prognosis.

Last revision and medical review: 10/2012

By Elodie Espesset

Synovial Sarcoma: A Detailed Review

Introduction

Soft tissue sarcomas are malignant tumors of non-epithelial, extraskeletal tissue of the body, including the muscle, fat, fibrous tissue, vessels and peripheral nervous system. They form a diverse group of mesenchymal malignancies, classified on a histologic basis according to the adult tissue they resemble or are supposed to derive from. These tumors are rare. With an annual incidence of around 2-3/100,000, they account for less than 1% of all malignant tumors and 2% of all cancer-related deaths, although in children soft tissue sarcomas represent about 8% of all malignancies.

An Important Note:

This article gives a description of pathological findings, clinical features and treatment options for patients with synovial sarcoma and provides an introduction for physicians not familiar with this disease. The authors are involved in the daily management of children and adolescents with soft tissue sarcomas. Therefore, in particular regarding treatment, the discussion represents mainly the point of view of a paediatric oncologist.

Synovial sarcoma (SS) represents one of the most frequent malignant tumors of soft tissues, accounting for about 8% of all soft tissue sarcomas. Weiss reports that SS is the most frequent non-rhabdomyosarcomatous soft tissue sarcoma in adolescents and young adults, accounting for 15-20% of cases.1 The peak of incidence is in the 3rd decade (approximately 30% of cases occur in patients less than twenty years of age), and males are affected more often than females (male/female ratio around 1.2:1). A recent paper describes clinical findings and outcome of 1268 cases (213 children/adolescents, i.e.less than 18 years, and 1055 adults) registered in the North-American Surveillance, Epidemiology, and End Results (SEER) 17 database from 1983 to 2005.2

Despite its name, synovial sarcoma does not arise from synovial tissue. As with most soft tissue sarcomas, the pathogenesis of SS is still unknown and there are no well-established risk factors; therefore, no screening program has been evaluated or could be recommended.

Pathology and Biology of Synovial Sarcomas

Figure 1

Figure 1: This is a picture of a biphasic synovial sarcoma, in which...

SS is clinically, morphologically and genetically a distinct sarcoma, characterized by the specific chromosomal translocation t(X;18) (p11;q11). In the last ‘WHO Classification of Soft Tissue and Bone Tumours’ SS is classified among malignant tumours of uncertain differentiation, lacking a precise normal tissue counterpart.3 Even if typical of soft tissues, SS are described also in other sites, such as the kidney, lung, and pleura.

SSs are classified based on their morphological appearance as:

  • Biphasic SS
  • Monophasic SS bu
  • Monophasic epithelial SS (exceptional)
  • Poorly differentiated SS

Figure 2

Figure 2: Monophasic synovial...

Biphasic SS shows both spindle and epithelial cells in varying proportions (Figure 1).

Monophasic SS shows only the spindle cell component. (Figure 2). The monophasic purely glandular epithelial SS is a theoretical entity and requires molecular genetics to be distinguished from adenocarcinoma.

Poorly differentiated SS shows one of three morphologic patterns: a large cell / epithelioid / rhabdoid pattern, a small cell pattern, and a high grade spindle cell pattern (Figure 3).

Figure 3

Figure 3: This is a poorly differentiated synovial sarcoma, small cell type...

Among the different grading systems available, the French system, FNCLCC (French Federation of Cancer Centers Sarcoma Group), is the most often used for adult-type soft tissue sarcomas.4 It is a score system in which the sum of D (differentiation; ‘D3’ by default in SS), M (mitoses: below 10/10HPF; between 10 and 19/10HPF; more than 19/HPF) and N (necrosis: absent; less than 50%; more than 50%) gives the grade 1, 2 or 3. Even if in therapeutic protocols SS is considered among high-grade sarcomas by definition, the FNCLCC grade is reported as the most predictive histological factor for metastasis in SS. Less than 10 mitoses/10HPF, absence of necrosis, absence of poorly differentiated areas, pediatric age, size smaller than 5 cm, and eradicated localized tumors resulted in a better prognosis.5

Translocations: The online Atlas of Genetics and Cytogenetics in Oncology and Haematology contains a webpage summarizing classification and other information about Synovial Sarcoma. Also, see the sidebar "Molecular Genetics", below.

Gross Findings: The diameter of SSs varies from 3 to 10 centimetres (cm). Tumors tend to be multinodular and can be cystic. When they grow slowly, they tend to have pushing margins and are circumscribed by a fibrous pseudocapsule. Poorly differentiated SS grows rapidly with infiltrative margins, showing haemorrhage and necrosis. 

Histological Findings: SSs are composed of two morphologically and immunophenotypically distinct cell types: spindle cells, uniform and relatively small, with oval nuclei and scarce cytoplasm, forming solid sheets, and epithelial cells, characterized by true epithelial differentiation.

Poorly Differentiated Synovial Sarcoma is considered as a form of progression, with a more aggressive behavior and a higher percentage of metastase.1 In the less cellular areas there can be hyalinization, myxoid changes and calcifications, with or without ossification and rarely chondroid changes. Focal tumoral calcification, with or without ossification, is present in about one third of SSs. The authors have prepared a table of the clinical and pathological characteristics of synovial sarcoma.

Molecular genetics: SS are characterized as a group by the presence of a specific translocation t(X;18), that fuses the SYT gene from chromosome 18 with SSX1 (about 2/3 of cases), SSX2 (about 1/3 of cases) or SSX4 (rare cases) gene from X chromosome. As a consequence of the translocation, a fusion transcript is formed at mRNA level, detectable by PCR tecniques. Cases with both SYT/SSX1 and SYT/SSX2 fusion transcripts have been described. SYT/SSX1 is reported significantly associated with biphasic SS. The association between SYT/SSX1 with reduced metastasis-free survival in localized tumors was not confirmed in all series, and the prognostic relevance of the fusion gene typing is still uncertain.6,7

Clinical Features and Diagnosis of Synovial Sarcoma

SS can arise anywhere in the soft part of the body, generally as a progressively expanding mass. The most common clinical presentation is a slow-growing mass in the soft tissues of the lower extremity, especially around the knee and the ankle. The tumor is often near a joint, tendon or bursa. Head and neck region, abdominal wall, retroperitoneum, mediastinumpleura, lungs and other organs are less common locations.

Various symptoms may be related to these locations, although the painless mass remains the most frequent presentation. Difficulty in swallowing and breathing, or alteration of voice, for example, might be associated with SS of the head and neck region. Pain may be related to the involvement of nerves. Because the tumor grows slowly, symptoms may be present for a long time before the diagnosis is made. This may delay diagnosis.

As it is a high-grade sarcoma, SS is characterised by local invasiveness and a propensity to metastasize. At the time of diagnosis, less than 10% of cases present with metastases (particularly to the lung), but metastatic spread can successively occur in 25-50% of cases.

Figure 4

Figure 4: Magnetic Resonance Imaging (MRI) of a 17-year old boy...

In order to determine local and distant extent of disease, a complete set of staging studies is necessary at diagnosis. Imaging studies are critical in determining tumor size and local extent. Ultrasonogram is often the first instrumental assessment to be used. Computed Tomography (CT) scan or Magnetic Resonance Imaging (MRI) of the primary site are mandatory for local extension assessment before any treatment. MRI of an extremity is usually considered superior in defining soft tissue extension (Figure 4).

After the accurate description of the local extent of the tumor, pathological assessment is necessary to define the histological diagnosis. The initial biopsy has the aim to define the diagnosis, but also should provide enough material for immunochemistry, cytogenetics, biological studies and central pathology review for patients to be included in multicenter clinical trials.

In the case of a large and deep soft tissue mass, biopsy should be always the initial surgical procedure, in order to avoid inadequate surgery. Open biopsy (incisional biopsy) or core needle biopsy (tru-cut, guided by ultrasound or CT scan) is preferred to fine needle aspirates that could establish the presence of malignancy, but rarely identify the subtype or provide the tissue required for additional studies. In any case, the initial biopsy should be carefully planned by an experienced surgeon, taking into account the possible subsequent definitive surgery, that must include the scar and the biopsy tract. For example, in SS of the extremities, the incision must be longitudinal to the limb and not traverse multiple compartments; very careful hemostasis must be ensured to minimize the risk of post-surgical hematoma and need for drains. In all cases, tissue should be sent fresh to the laboratory. When this is not possible, formalin-based fixative must be used.

Staging

After the radiological evaluation of tumor extent and biopsy, the diagnostic work-up is completed by staging investigations, aimed to detect regional and distant metastases. Chest CT scan, Technetium bone scan and abdominal ultrasound have been generally required to identify lung, bone, and abdominal metastases, respectively. Attention to regional lymph nodes of the primary site is also important. Positron emission tomography (PET) is not yet considered a standard staging investigation for SS.

A recent study from European pediatric groups on 258 SS patients less than 21 years old discussed whether staging diagnostic procedures are really necessary in all patients.8 The analysis showed that 5.8% of cases had distant metastases at diagnosis, and 86% localized at lung. The presence of metastases was unassociated with patients’ gender or age, tumor grade or site, but it was influenced by T-status, and especially primary tumor size: the risk of metastases was 32 times higher in cases of tumor > 5 cm than for tumors £ 5 cm. These findings would suggest that tumor diameter can be used as a variable for identifying patients at greater risk of metastases and warranting more accurate radiological investigations, and patients at low risk for which ionizing radiation exposures with carcinogenic potential may be avoided, at staging as well as at follow-up. According to these results, chest CT scanning may be omitted for patients with tumors less than 5 cm and, given the very low risk of bone metastases, bone scans may be recommended only in cases with evidence of lung metastases or symptoms suspected for bone lesions.

A risk-adapted treatment strategy is based on pre-treatment staging and post-surgical clinical status. Pediatric oncologists usually stage SS according to the clinical TNM classification (based on local invasiveness, T1 and T2, and tumor size, A or B, i.e. less or more than 5 cm; absence or presence of nodal and distant involvement: N0 and N1, M0 and M1, respectively.9 The Intergroup Rhabdomyosarcoma Study (IRS) post-surgical grouping system is based on the degree of surgical resection10:

  • Group I - completely-excised tumors with negative microscopic margins
  • Group II - grossly-resected tumors with microscopic residual disease and/or regional lymph nodal spread
  • Group III - gross residual disease after incomplete resection or biopsy
  • Group IV - metastases at onset

Adult oncologists often stage using the American Joint Committee on Cancer Staging system which incorporates the histological grade (which is presumably high in all SS patients) in addition to size and depth (most SS are deep-seated).

A recent study of the Associazione Italiana Ematologia Oncologia Pediatrica – Soft Tissue Sarcoma Committee (AIEOP-STSC) on 115 pediatric SS cases evidenced the prognostic role of tumor site: the outcome of patients with axial/non-extremity SS (e.g. head–neck, trunk, lung-pleura, retroperitoneum) was worse than that of patients with limb tumors (5-year OS of 55% and 84% respectively), mainly due to local failure.11 This study suggests that tumor site should be considered when defining a risk-adapted treatment strategy for SS.

The current protocol of the European pediatric Soft Tissue Sarcoma Study Group (EpSSG) stratify patients according to surgical stage (IRS), tumor size and tumor site.

Prognosis

The prognosis of SS patients is related to the feasibility of surgical resection, tumor size, and local invasiveness. Patients with small tumors that can be completely removed at diagnosis have an excellent prognosis. For tumors larger than 5 cm, the risk of developing distant metastases is higher. Pediatric series11-16 reported survival higher than 80% for IRS Group I-II patients, but around 60-70% for cases > 5 cm. For patients with unresectable disease at diagnosis (IRS group III), survival has been reported between 50 and 60%,17 but it clearly is less for cases localized in head-neck region, lung and mediastinum, abdomen. The prognosis is particularly poor for SS patients with distant metastases at onset2 and for patients whose tumors relapse. A recent analysis of the Italian pediatric group on 44 relapsing cases (out of a series of 118 patients) showed that overall survival of recurrent disease was 29.7% and 21.0% 5 and 10 years after relapsing, respectively. The variables influencing survival were the timing and type of relapse (late and local relapse had a better survival) and the chances of a secondary remission, which correlated strongly with the feasibility of complete surgery. These findings permit to identify a possible risk-adapted stratification enabling a better planning of second-line treatment. An aggressive surgical approach should be recommended, while experimental therapies can be offered to patients with little chance of salvage.18

Treatment

The optimal treatment approach to SS remains to be determined. As in other soft tissue sarcomas, the standard treatment for localized disease is surgery, and radiotherapy has a role in improving local control after less than compartmental resections. The role of chemotherapy is still not clear and the rarity of these tumors hinders the accrual of adequate numbers for a randomized trial. However, it is possible to say that surgical resection plus or minus adjuvant radiotherapy and/or doxorubicin/ifosfamide based chemotherapy are the current mainstays of treatment.

Sarcoma Centers: Synovial sarcoma is a rare tumor and its treatment is necessarily multidisciplinary and complex. Patients should be referred to selected institutions with adequate experience in treating patients with soft tissue sarcomas, and with multidisciplinary skills in enrolling patients in clinical trials.

Surgery

Surgery is the keystone of treatment for SS. It aims to obtain adequate margins with little or no long-term sequelae, and should be attempted as the primary approach only if complete and non-mutilating resection is considered feasible. Otherwise, after diagnostic biopsy, chemotherapy and/or radiotherapy should be given to shrink the tumor and make it more amenable to subsequent surgery. Achieving "adequate margins" is a crucial issue, strictly influenced by the type of healthy tissue surrounding the tumor. It is very difficult to apply a metric definition of a "safe distance" between tumor and resection margins.19 The June 2004 Milan Consensus Conference on Adult Soft Tissue Sarcomas suggested a definition to which adequate margins are "those > 1 cm of healthy tissue around the tumor, in all directions, when the tissue is a muscle, and > 1 mm of healthy tissue around the tumor when the tissue is periostium, vessel sheath, epineurium, or muscular fascia." Inadequate surgical margins adversely affect local outcome — and consequently also overall survival — though some studies on adult soft tissue sarcomas failed to find a strong correlation between quality of surgery and final outcome. However, adequate surgery could be defined an R0 resection that renders the patient classified as IRS Group I. This includes both compartment resections (en bloc resection of the tumor and the entire compartment of origin, where tumor was entirely anatomically confined) and wide excisions (en bloc excisions through normal tissue, beyond the reactive zone but within the muscular compartment, removing the tumor with its pseudocapsule).

Surgery: When and Where - The quality of the surgical operation is crucial. Patients with deep and large soft part masses, i.e. in excess of 5 cm (highly suspect of being sarcomas) should be referred to specialist centers for local treatment, preferably before undergoing biopsy.

Chemotherapy

Concerning the role of chemotherapy, it is quite surprising that, over the years, completely different strategies have been developed in pediatric oncology protocols compared with the adult setting. Since quite high rates of response to chemotherapy have been recorded in pediatric series, pediatric oncologists have considered SS as a "rhabdomyosarcoma-like" tumor, in other words a chemosensitive tumor. Therefore pediatric patients have received adjuvant chemotherapy regardless of stage, even after the complete excision of very small tumors.11-15,20-21 Differently, adjuvant chemotherapy has generally only been used in adult patients in trials that included all soft tissue sarcoma histotypes and a no-therapy control arm.22-27

Only recently adult oncologists have recognized a possible role for adjuvant chemotherapy for high-risk cases, i.e. large tumor size.26 While some studies on adult SS showed no any evidence of a survival benefit for adjuvant chemotherapy and stated that chemotherapy should not be delivered outside a clinical trial setting,24,27-29 others suggested that SS may be considered more chemosensitive than other adult soft tissue sarcomas, with a survival benefit from neoadjuvant/adjuvant chemotherapy, especially when patients were selected according to risk factors.30-32

It remains to be understood whether the different historical approaches of pediatric versus adult medical oncologists in treating SS patients had determined differences in outcome. In the large SEER series, the estimated 5-year cancer-specific survival was 83% for children/adolescents and 62% for adults (P < .001).2 However, on one side it is possible that this difference in outcome might be related to biological variables and different incidence of prognostic factors, on the other side the survival rates of adult patients in the most recent adult series published by major referral institutions or cooperative groups did not differ substantially from what reported by pediatric groups, though chemotherapy was used in a lower proportion of cases.

It remains to be demonstrated whether the worse outcome of adult synovial sarcoma reported in epidemiological analyses relates to a different access to care, since it has been variously reported that adults with cancer may have fewer chances of being enrolled in clinical trials and, more in general, of being treated at referral centers than children.33,34

Concerning pediatric series, the multicenter retrospective multivariate analysis coordinated by the M. D. Anderson Cancer Center which included the updated results of the previously published pediatric series examined the clinical history and treatment strategy of children and adolescents with SS.15 Overall survival (OS) of the 219 patients was 80% at 5 years, higher than that reported in adult series, and chemotherapy response rate was 60%, higher than that usually obtained in adult sarcomas. However, the analysis suggested that adjuvant chemotherapy had no impact on survival in IRS Group I-II patients, event-free survival (EFS) was 84% for the 37 patients treated without and 78% for 122 patients treated with adjuvant chemotherapy.15

Figure 5

Figure 5: Study from the Istituto Nazionale Tumori of Milan, Italy....

A study from the Istituto Nazionale Tumori of Milan of 271 patients compared the clinical findings, treatment modalities and outcomes of SS at different ages.35 No major differences in clinical presentation were noted, except a tendency for larger tumor size for older patients, suggesting in principle no major biological differences correlated with age. However, when patients with grossly-resected disease were considered, significant differences in the use of adjuvant chemotherapy were seen, with a strong correlation of survival rates with age groups and use of chemotherapy. The metastases-free survival (MFS) was 60% in patients given chemotherapy and 48% in those who were not. Likewise, MFS dropped from 69% to 53% to 43% for the 0-16 year-old (78% given chemotherapy), 17-30 year-old (21% given chemotherapy) and >30 year-old (15% given chemotherapy) age brackets, respectively; see Figure 5.35 Of course, this retrospective analysis cannot be construed as a formal demonstration of the efficacy of adjuvant chemotherapy in SS, but would nonetheless suggest that it has a role.

Response to Chemotherapy

The biology of synovial sarcoma probably falls between most typical adult soft tissue sarcomas and paediatric small round cell tumors such as rhabdomyosarcoma or Ewing’s sarcoma. The response rate to chemotherapy, in fact, is approximately 60% for synovial sarcoma, less than 40% for adult soft tissue sarcomas and 80% for rhabdomyosarcoma.

Though it may be true that unfavorable clinical findings may affect adult patients more than children (and age "per se" could probably be considered a prognostic factor for soft tissue sarcomas), a different biology of SS when arising in adults as opposed to children is, at the very least, unlikely, and therefore, there is no reason to treat the same disease at the same stage in different ways according to the age of the patient.

A further analysis comes from the Italian and German pediatric soft tissue sarcoma cooperative groups in which retrospective data on 150 pediatric patients with grossly-resected SS were reviewed.16 This study was unable to cast any light on the role of adjuvant chemotherapy, however, because nearly all but very few patients received chemotherapy. Nevertheless, it pointed to a subset of patients at very low risk of metastases: four local relapses and no metastatic relapses were seen among the 48 IRS group I patients with tumors < 5 cm. For this group, the use of adjuvant chemotherapy, as required in previous European pediatric trials, could be considered an over treatment.

Figure 6: Risk-adapted treatment program for synovial sarcoma

Figure 6: Risk-adapted treatment program for synovial sarcoma...

The above discussed data were considered in the development of the recently-established protocol from the European pediatric Soft Tissue Sarcoma Study Group (EpSSG), the first European protocol that is specifically tailored for non-rhabdomyosarcoma soft tissue sarcomas. This protocol will recruit patients over all Europe. Its treatment rationale is influenced by previous pediatric experiences, but have taken suggestions from adult experiences and moved towards a treatment concept partially similar to that adopted in the adult setting36: the ifosfamide-doxorubicin chemotherapy is currently adopted as standard regimen, and its indication is given according to the patient’s risk stratification, based on tumor size and site and surgical stage, see Figure 6.37 In low-risk patients (completely resected tumors under 5 cm in size), chemotherapy is omitted.16

Radiotherapy

Radiotherapy plays a well-defined role in local control in soft tissue sarcomas. In adult patients with soft tissue sarcoma, radiotherapy is usually recommended after incomplete resection, but often also after wide excision, especially in case of large tumour. Certainly, the indication for radiotherapy has to be stricter in children and young adolescents with SS than in adults, given the higher risk of severe late effects of radiotherapy.

The above quoted INT Milan series reported only a favorable trend for the addition of radiotherapy in patients who initially had complete resection: in IRS group I patients, 5-year local relapse free survival (LRFS) was 78% in patients treated with and 67% in those treated without post-operative radiotherapy. However, a clear benefit was observed for patients whose initial resection was marginal: IRS Group II patients had a 5-year LRFS of 57% when radiotherapy was delivered and 7% when it was not.35 According to the EpSSG protocol, surgery could be considered as the sole local treatment for group I patients (though the need of irradiation in case of tumor > 5 cm is still an open question), while post-operative radiotherapy is required for IRS Group II patients.37

The local treatment strategy is more complicated in patients whose tumors are considered unresectable at diagnosis, and thus receive initial chemotherapy. For these patients, delayed surgery is the treatment of choice and every effort should be done to obtain complete resection. However, the need for additional radiotherapy in case of delayed complete resection remains an open question. Likewise, there are relative merits of pre-operative versus post-operative radiotherapy: post-operative radiotherapy carries a lower risk of complications, but pre-operative irradiation can improve the chances of achieving free margins at the secondary resection, may reduce the risk of intra-operative contamination, and smaller radiotherapy fields and lower doses can often be used. We believe that the choice of local treatment should be discussed in a multidisciplinary setting and the decision should be customized. Various factors should be considered, i.e. anatomical site, tumor size, and patient’s age, with the aim to give to all patients the "best possible local treatment."

Future Issues

As with other soft tissue sarcomas, in the next years we expect to improve our understanding of SS, and we particularly need novel therapeutic approaches. The specific chromosomal translocation and fusion proteins occurring in SS38 and the proteins overexpressed by the tumor cells (epidermal growth factor receptor EGFR, HER-2/neu, Bcl-2),39,40 may become the targets of new molecular agents specifically designed to influence the tumor’s biology.41 Clinical investigative trials on targeted therapy are ongoing. Investigations are underway on the role of new drugs, such as trabectidine, multi-target anti-tyrosine kinases inhibitors, and on monoclonal antibody against frizzled homologue 10 (FZD10), a cell-surface receptor in the Wnt pathway, or adoptive immunotherapy using tumor-infiltrating lymphocytes against NY-ESO-1 cancer/testis antigen (expressed in 80% of SS).42-45 Similarly, further studies are needed to investigate the role of the Bcl-2 antisense oligonucleotide therapy, as most SS overexpress the anti-apoptotic protein Bcl-2, that correlates with tumor growth, chemoresistance and poor outcome in various cancers.6

Targeted Therapy: Synovial sarcoma is a particular tumor with important promise for targeted therapy directed against the fusion protein produced by the specific translocation or against tyrosine kinases receptors overexpressed by tumor cells.

The developing of cooperative trials involving both pediatric and adult patients with SS could be the right strategy to increase biological studies and obtain, in a rare disease as SS, the large accrual of cases necessary to design adequate clinical trials.

Last revision and medical review: 10/2012
By Andrea Ferrari, MD
Pediatric Oncology Unit
and Paola Collini, MD
Pathology Department

Istituto Nazionale per lo Studio e la Cura dei Tumori
Via G. Venezian, 1 -20133 Milano MI, Italy

Bibliography and Related Works

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2. Sultan I, Rodriguez-Galindo C, Saab R, et al. (2009) Comparing children and adults with synovial sarcoma in the Surveillance, Epidemiology and End Results Program, 1983 to 2005: an analysis of 1268 patients. Cancer 115:3537-3547.

3. WHO Classification of Tumours. Pathology and Genetics. Tumours of Soft Tissue and Bone. CDM Fletcher, KK Unni, and F Mertens eds. IARC Press, Lyon, 2002.

4. Guillou L, Coindre JM, Bonichon F, et al. Comparative study of the National Cancer Institute and French Federation of Cancer Centers Sarcoma Group grading systems in a population of 410 adults patients with soft tissue sarcoma. J Clin Oncol.1997; 15:350-362.

5. Guillou L, Benhattar J, Bonichon F, et al. Histologic grade, but not SYT-SSX fusion type, is an important prognostic factor in patients with synovial sarcoma: a multicenter, retrospective analysis. J Clin Oncol. 2004;22(20):4040-4050.

6. Mancuso T, Mezzekani A, Riva C, et al. Analysis of SYT-SSX fusion transcripts and bcl-2 expression phosphorylation status in synovial sarcoma. Lab Invest 80:805-813, 2000.

7. Mezzelani A, Mariani L, Tamborini E, et al. SYT-SSX fusion genes and prognosis in synovial sarcoma. Br J Cancer 85:1535-1539, 2001.

8. Ferrari A, G.L.De Salvo, O.Oberlin, M.Casanova, A.De Paoli, A.Rey, V.Minard, D.Orbach, M.Carli, B.Brennan, M.M.Vannoesel, C.Morosi, M.C.Stevens, G.Bisogno. Synovial sarcoma in children and adolescents: A critical reappraisal of staging investigations in relation to the rate of metastatic involvement at diagnosis. Eur J Cancer, 48(9):1370-1375, 2012.

9. Harmer MH. TNM Classification of pediatric tumors. Geneva, Switzerland, UICC International Union Against Cancer, 1982:23-28.

10. Maurer HM, Beltangady M, Gehan EA, et al. The Intergroup Rhabdomyosarcoma Study I: A final report. Cancer 61:209-220, 1988.

11. Ferrari A, G.Bisogno, R.Alaggio, G.Cecchetto, P.Collini, A.Rosolen, C.Meazza, P.Indolfi, A.Garaventa, L.De Sio, P.D’Angelo, P.Tamaro, M.Casanova, M.Carli. Synovial sarcoma of children and adolescents: the prognostic role of axial sites. Eur J Cancer 44(9):1202-1209, 2008.

12. Ladenstein R, Treuner J, Koscielniak E, et al. Synovial sarcoma of childhood and adolescence: report of the German CWS-81 study. Cancer 71:3647-3655, 1993.

13. Pappo AS, Fontanesi J, Luo X, et al. Synovial sarcoma in children and adolescents : the St. Jude Children’s Research Hospital experience. J Clin Oncol 12:2360-2366, 1994.

14. Ferrari A, Casanova M, Massimino M, et al. Synovial sarcoma: report of a series of 25 consecutive children from a single institution. Med Pediatr Oncol 32:32-37, 1999.

15. Okcu MF, Munsell M, Treuner J, et al. Synovial sarcoma of childhood and adolescence: a multicenter, multivariate analysis of outcome. J Clin Oncol 21:1602-1611, 2003.

16. Brecht IB, Ferrari A, Int-Veen C, et al. (2006) Grossly-resected synovial sarcoma treated by the German and Italian pediatric soft tissue sarcoma cooperative group: discussion on the role of adjuvant therapies. Pediatr Blood Cancer 46:11-17.

17. Ferrari A, R.Miceli, A.Rey, et al. Non metastatic unresected pediatric non-rhabdomyosarcoma soft tissue sarcomas: results of a pooled analysis from United States and European groups. Eur J Cancer, 47:724-731, 2011.

18. Ferrari A, Salvo GL, Dall'igna P, et al. Salvage rates and prognostic factors after relapse in children and adolescents with initially localised synovial sarcoma. Eur J Cancer. 2012 Jul 24. [Epub ahead of print]

19. Gronchi A, Casali PG, Mariani L, et al. Status of surgical margins and prognosis in adult soft tissue sarcomas of the extremities: a series of 911 consecutive patients treated at a single institution. J Clin Oncol, J Clin Oncol. 2005;23(1):96-104.

20. Brennan B, Stevens M, Kelsey A, Stiller CA.Synovial sarcoma in childhood and adolescence: a retrospective series of 77 patients registered by the Children's Cancer and Leukaemia Group between 1991 and 2006. Pediatr Blood Cancer. 2010;55(1):85-90.

21. Orbach D, Mc Dowell H, Rey A, et al.Sparing strategy does not compromise prognosis in pediatric localized synovial sarcoma: experience of the International Society of Pediatric Oncology, Malignant Mesenchymal Tumors (SIOP-MMT) Working Group. Pediatr Blood Cancer. 2011;57(7):1130-6.

22. Sarcoma Meta-analysis Collaboration. Adjuvant chemotherapy for localised resectable soft-tissue sarcoma of adults: meta-analysis of individual data. Lancet 350:1647-1654, 1997.

23. Bergh P, Meis-Kindblom JM, Gherlinzoni F, et al. Synovial sarcoma: identification of low and high risk groups. Cancer 85:2596-2607, 1999. 

24. Lewis JJ, Antonescu CR, Leung DHY, et al. Synovial sarcoma: a multivariate analysis of prognostic factors in 112 patients with primary localized tumors of the extremity. J Clin Oncol 18:2087-2094, 2000.

25. Spillane AJ, A’Hern R, Judson IR, et al. Synovial sarcoma: a clinicopathologic, staging, and prognostic assessment. J Clin Oncol 18 :3794-3803, 2000.

26. Frustaci S, Gherlinzoni F, De Paoli A, et al: Adjuvant chemotherapy for adult soft tissue sarcomas of extremities and girdles: results of the Italian randomized cooperative trial. J Clin Oncol  19:1238-1247, 2001.

27. Trassard M, Le Doussal V, Hacène K, et al. Prognostic factors in localized primary synovial sarcoma: a multicenter study of 128 adult patients. J Clin Oncol 19:525-534, 2001.

28. Italiano A, Penel N, Robin YM, et al. Neo/adjuvant chemotherapy does not improve outcome in resected primary synovial sarcoma: a study of the French Sarcoma Group. Ann Oncol. 2009 Mar;20(3):425-30.

29. Palmerini E, Staals EL, Alberghini M, et al.Synovial sarcoma: Retrospective analysis of 250 patients treated at a single institution. Cancer. 2009 Jul 1;115(13):2988-98.

30. Spurrell EL, Fisher C, Thomas JM, Judson IR. Prognostic factors in advanced synovial sarcoma: an analysis of 104 patients treated at the Royal Marsden Hospital. Ann Oncol 2005;16:437-444.

31. Eilber FC, Brennan MF, Eilber FR, et al. Chemotherapy is associated with improved survival in adult patients with primary extremity synovial sarcoma. Ann Surg. 2007;246:105-113.

32. Canter RJ, Qin L, Maki R et al. A Synovial Sarcoma-Specific Preoperative Nomogram Supports a Survival Benefit to Ifosfamide-Based Chemotherapy and Improves Risk Stratification for Patients. Clin Cancer Res December 15, 2008 14; 8191.

33. Ferrari A, A.Bleyer. Participation of adolescents with cancer in clinical trials. Cancer Treatement Review 33(7):603-608, 2007.

34. Ferrari A, G.Bisogno, C.Meazza, M.Vajna de Pava, I.Sultan, G.L.De Salvo, C.A.Clerici, L.Veneroni, M.Casanova. The challenge of access to care for soft tissue sarcomas bridging pediatric and adult age: the Italian pediatric oncology view. Expert Review Anticancer Therapy 12(2):243-54, 2012.

35. Ferrari A, Gronchi A, Casanova M, et al. Synovial sarcoma: a retrospective analysis of 271 patients of all ages treated at a single institution. Cancer, 101:627:634; 2004.

36. Ferrari A. Harmonizing adult and pediatric approaches to the treatment of soft tissue sarcoma. Expert Review Anticancer Therapy, 9(11):1541-1543, 2009.

37. Ferrari A, Casanova M. New concepts for the treatment of pediatric non-rhabdomyosarcoma soft tissue sarcomas. Expert Rev Anticancer Ther, 5(2),307-318, 2005.

38. Kawaguchi S, Wada T, Ida K, et al. Phase I vaccination trial of SYT-SSX junction peptide in patients with disseminated synovial sarcoma. J Transl Med. 2005 12;3(1):1.

39. Tamborini E, Bonadiman L, Greco A, et al. Expression of ligand-activated KIT and platelet-derived growth factor receptor b tyrosine kinase receptors in synovial sarcoma. Clin Cancer Res 10:938-943, 2004.

40. Thomas DG, Giordano TJ, Sanders D, et al. Expression of receptor tyrosine kinases growth factor receptor and HER-2/neu in synovial sarcoma. Cancer 2005;103(4):830-808.

41. Albritton KH, Randall RL: Prospects for targeted therapy of synovial sarcoma. J Pediatr Hematol Oncol 27:219-222, 2005.

42. Robbins PF, Morgan RA, Feldman SA, et al. Tumor regression in patients with metastatic synovial cell sarcoma and melanoma using genetically engineered lymphocytes reactive with NY-ESO-1. J Clin Oncol 2011;29(7):917-924.

43. Fukukawa C, Nakamura Y, Katagiri T. Molecular target therapy for synovial sarcoma. Future Oncol 2005;1(6):805-812.

44. Fukukawa C, Hanaoka H, Nagayama S, et al. Radioimmunotherapy of human synovial sarcoma using a monoclonal antibody against FZD10. Cancer Sci 2008;99(2):432-440.

45. Hartmann JT. Systemic treatment options for patients with refractory adult-type sarcoma beyond anthracyclines. Anticancer Drugs 2007;18(3):245-254.

Synovial Sarcoma Stories and Support

Laurie writes about her daughter

My hero is my daughter, Codi Leigh. Our lives changed in November of 2008 when she was diagnosed with synovial sarcoma. The doctor didn’t know what he was removing when he took a tumor out of her foot. She was in good spirits, looking forward to the pain in her foot going away, then wearing high heels out for her 21st birthday. A week later the pathologist called. The tumor was a rare form of cancer, and he told us to get to the Mayo clinic ASAP.

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A few days later, there we were. The team of doctors and nurses were awesome, but things needed to move quickly as the tumor was removed in pieces allowing the vicious cancer cells to hasten through her body. Codi was joking around with the surgeon when she asked if they were going to have to cut off her foot. Needless to say, the answer was yes. Time was of the essence. With quiet dignity and a tear rolling down her face, Codi’s answer was, "Let’s do it. I want to be home for Thanksgiving because my brother is coming home."

Codi’s strength and never-give-up attitude was the glue that held everything together. When going into surgery, we didn’t know if the amputation was going to be just her foot or her whole leg (it ended up as a below the knee). While they were wheeling her away, she was discussing with the nurse how she was going to design shoes for prosthetics, something for the 20-something age group. Codi had such courage, an upbeat attitude and way of looking at things, whether she was shaving the last of her hair off, puking from chemo, making jokes about being stumpy, or learning to walk with a prosthesis. She fought the good fight and won, with humor, dignity, strength and courage.

Heather joins Team Sarcoma

Heather's ClassBefore Sarcoma, I loved to run and to work out. In fact, I had done a yoga class early in the morning the day I entered the hospital with mysterious bleeding that would end up being synovial sarcoma of my right kidney.

During chemo, as I lost more weight and became weaker, I would dream of running in the mountains, and would distract myself from nausea by "taking" yoga classes in my head. I soon returned to the gym in an attempt to rebuild bone density lost during treatment. Lifestyle Family Fitness, Hunter’s Creek in South Orlando area proved to be a true "no judgment" zone as I slowly grew stronger. I fell in love with the Les Mills Body Pump classes–and recently became an instructor. During my training, we were encouraged to share a bit about why we were training. I told my story, which became an incredible opportunity to educate people about sarcoma…there were more than a few tears shed that day!

In 2010, I decided to participate in the Team Sarcoma event on Facebook and asked my early morning "regulars" if they would stand with me in my photo, just like they stood with me in encouragement throughout my training journey. Fittingly, I picked the song, "Invincible" to start the class out that morning: it was the way I felt as I looked out on my friends wearing their best blue workout shirts to match my "Sarcoma Knows No Borders" bracelet! We had 15 people show up for the (very) early morning class, where I shared bits of my story and Sarcoma Facts throughout.

Andrea writes about her hero

Nineteen years ago, a young girl heard the news that no teen wants to hear…she had cancer. The lump that had been growing in her inner thigh was a cancerous tumor. The diagnosis: synovial sarcoma. Within days of receiving the diagnosis, the teen was sent to Massachusetts General Hospital, the only hospital within hundreds of miles of home that could treat this cancer. On a damp, dismal day in March of 1991, she met many doctors who would be responsible for saving her life.

The one doctor she was immediately drawn to was soon to be her future orthopedic oncologist, Dr. Mark C. Gebhardt. Dr. Gebhardt understood the severity of the situation. He spoke to the girl’s family with a sense of determination. He knew the fears this girl felt, even though she never uttered a word about them. She knew there was a chance she could lose her leg to this type of cancer, but Dr. Gebhardt never mentioned this possibility. Instead, he treated the cancer immediately with rounds of radiations and surgeries. She met with him every week for many weeks and by June 1991, she was considered cancer free. He had not only saved her leg but also her life.

I was seventeen years old when I was that young girl diagnosed with synovial sarcoma. Though many years have passed since my diagnosis, I am constantly reminded of my battle with cancer. Every day I think about how fortunate I am to have been blessed with such a beautiful life. I have Dr. Gebhardt to thank for that. He is truly a hero to me. He has made it possible for me to spend the last two decades loving my family and friends and for that, I will forever be grateful to him.

Hilary shares her story

Hilary

Does one ever recover from the initial sarcoma experience? Physically, I am fully recovered. Because I have played competitive tennis most of my life and sail, ride, kayak, golf, I wanted full use of my right arm. I went to a trainer to get a workout for the period of radiation because I was told I would loose extension and flexion ability. Thankfully, I have full use of my right arm, and I am left-handed. My scans and dermatology checks at Dana Farber are now every six months. Four weeks before scans I go through too many negative scenarios in my head even though I am so active and healthy now. Read more of Hilary's story.

Jennifer writes about her surgery

August 1, 2007 was the date of the surgical resection of a tumor that had grown behind my right knee. I was diagnosed with synovial sarcoma five months before, just a few days after my 27th birthday. I will never forget the tears that fell from my face and onto the downy hair of my 10 month old son, who sat on my lap as I absorbed the news. Chemotherapy treatment followed shortly after, with the hope that it would shrink my 8 cm tumor – a tumor that had managed to wrap itself around a major leg nerve.

As I sat on my gurney waiting to be wheeled into the operating room, I thought about the "what ifs". What if they can’t remove the tumor in its entirety? What if they can’t spare function to my leg? I was well aware of these possibilities. My surgeon had explained them all to me just one week prior to my operation. His first priority was to save my life; his second was sparing my limb. He discussed amputation, prosthetics and physical rehabilitation. All I wanted to hear was that he would do everything he could to save my leg, and I told him so. He said that he would give it his all.

Awakening from the fog of anesthesia, I looked at my right leg. It was wrapped in layers of gauze. "Move your toes," I told myself. My toes moved and wiggled. It was my own, be it impaired, version of a victory dance. With my beeping morphine pump cheering me on, I slowly flexed my foot. This time the tears that fell from my face were those of utter joy. I knew that my surgeon had kept his word. I had my life and my leg!

Codi writes about her hero

When I was diagnosed with synovial sarcoma and lost my right leg, my mother became more of a hero to me than I ever thought imaginable. She is a special education teacher who lived more than 400 miles away; but when I went to my first doctor’s appointment in Rochester, MN, she was here to drive me. She sat with me when the doctor told me of the news, "Codi, we are going to have to amputate part of your right leg because of the cancer." She held her emotions strong when I was breaking down, just to know what had to be done for me. Her motherly way was to protect her young. Long hours, constant driving and my intense mood swings engulfed her life.

My mother did not complain, question, or tire of this. She stuck it to me straight. She would not let this awful destiny ruin me like I thought unavoidable. I decided to move back home with her and she did not treat me as a handicap cancer-ridden person as other people did. When I was feeling sorry for myself, on the verge of giving up by letting this disease rule my life, she was there to encourage me to accept and overcome, all the while keeping her composure.

In the back seat of the car on one of the countless chemo trips I awoke from sleeping to hear her cry. She chose to let her emotions out when I was not aware, just so she could stay strong for me. If it wasn’t for her, I would still be in my old room, in my bed wishing I could be out dancing. Since she kept me strong, I’m now out dancing and looking into a future in prosthetics.

The Synovial Sarcoma Survivors Network

Members of this online support group are mostly from English-speaking countries (US, Canada, UK, Australia, New Zealand, India), but some non English-speaking countries are also represented (Korea, Belgium, Netherlands, France, Malaysia, Argentina, Greece, Brazil, Poland, Sudan). Members are not required to provide their ages, but most members seem to be young adults. A few teenagers and a few older adults are also part of the group. Not all members are patients; many members are the spouses or parents of patients.

When somebody joins the group, a personal page is created with the new members information. Usually this includes location of the tumor, time of diagnosis and a brief history the patient's experience with synovial sarcoma and its treatment. Many members upload personal pictures (family or disease related). They also use this page to give updates on their current disease status. The page also tracks public exchanges between the member and other members.

Private exchange is possible through the use of the 'friend request' feature. Once members have agreed to be friends, they can exchange private messages without having to exchange e-mail addresses. Some people seem to be more comfortable communicating this way.

The website offers a discussion forum, with a search tool so a new member can check whether a particular theme was already discussed. It also carries a blog feature where members can share information related to the disease. The blog has a search tool so that writers can add information based on a theme. So if there is already a blog entry for a particular subject, the next blog entry on the same subject can be added as a comment. The website provides a live chat feature, and members must be online at the same time in order to chat.

New members are welcomed by moderators. Most of the moderators are experienced with synovial sarcoma and can provide personal support, but a few are more experienced with websites and can provide technical help. Discussions are usually disease-related, which means that they are both serious and informative. As in many support groups, the more active members tend to be the ones with advanced disease. Some of them have already passed away, and grief can affect the tone of the group.

Connect on Facebook

Here are a few of our favorite Facebook groups that provide opportunities to exchange messages with synovial sarcoma patients, survivors and their loved-ones.

Find Treatment and Support Resources

We maintain listings of sarcoma treatment centers, local support groups and organizations that provide financial assistance to sarcoma patients and their loved-ones.

Synovial Sarcoma Research

The Liddy Shriver Sarcoma Initiative is pleased to support synovial sarcoma research and has funded a $250,000 study on synovial sarcoma. There is much to be learned about this rare cancer. We hope to fund additional synovial sarcoma studies in the future, and we believe that research will lead to newer and better treatments for those who are diagnosed with this disease.

The following research study was funded by the Initiative after experts agreed that it was clinically relevant and scientifically sound:

An International Collaborative Study of Synovial Sarcoma

International Collaborative Study of Synovial Sarcoma $250,000 Grant: In this study, four investigators in three countries are working to understand the genetic pathways that make it possible for synovial sarcomas to develop and thrive. They hope to discover targets for new and effective treatments.

This grant was awarded by Synovial Sarcoma Research Foundation and the Liddy Shriver Sarcoma Initiative in May 2014. It was made possible by generous donations from the Wendy Walk (in memory of Amanda Noble) and the Alan B. Slifka Foundation (in memory of Ann Davis), donations in honor of Elodie Espesset and Jason Fesel, and donations in memory of Lucia Kramer, Artem Petrossian, Louie Pellegrini IV, Jensen Barrett, Rhonda Williams, Alison Schmeling Foerster, Wayne Coffey III, and Jennifer Colladay.


  • Figure 1: Biphasic synovial sarcoma
    This is a picture of a biphasic synovial sarcoma, in which we can see the coexistence of both the epithelial glandular component and the spindle cell component.
  • Figure 2: Monophasic synovial sarcoma
    Figure 2: This is a picture of a monophasic synovial sarcoma, in which only the spindle cell component is present.
  • Figure 3: Poorly differentiated synovial sarcoma
    Figure 3: This is a poorly differentiated synovial sarcoma, small cell type, characterized by a prominent hemangiopericytomatous pattern formed by dilated vascular structures, between which there are cells that are roundish and small, like those seen in a small round cell tumor, i.e. Ewing's sarcoma. In these cases molecular genetic analyses could be required to differentiate between these two entities.
  • Figure 4: Magnetic Resonance Imaging (MRI)
    Magnetic Resonance Imaging (MRI) of a 17-year old boy with a synovial sarcoma of the proximal thigh: MRI is mandatory for the adequate assessment of the local extension of the tumor. MRI seems superior to CT scans in defining soft tissue extension.
  • Figure 5: Study from the Istituto Nazionale Tumori
    Study from the Istituto Nazionale Tumori of Milan, Italy (retrospective analysis of 271 patients of all ages): survival rates correlated with age and with the use of chemotherapy, that was clearly different in the different age groups (Ferrari A, et al. Cancer, 101:627:634; 2004).
  • Figure 6: Risk-adapted treatment program for synovial sarcoma
    European pediatric Soft Tissue Sarcoma Study Group EpSSG, NRSTS 2005 protocol (amendment September 2009).