Grossly-resected synovial sarcoma treated by the German and Italian Pediatric Soft Tissue Sarcoma Cooperative Groups: discussion on the role of adjuvant therapies

Differently from adult oncologists that considered synovial sarcoma (SS) a tumor with uncertain chemosensitiveness, since two decades pediatric oncologists in Europe assumed that chemotherapy played an important role in SS treatment, so most pediatric patients were included in rhabdomyosarcoma protocols, receiving adjuvant chemotherapy regardless of risk factors. The German and Italian groups reviewed the data of grossly resected SS patients in order to define a risk-adapted treatment program for the next European protocol. A total of 150 patients < 21 years with localized SS who underwent initial gross resection between 1975 and 2002 were the object of this study. All but four cases received adjuvant chemotherapy. Post-operative radiotherapy was administered to 50% Group I and to 92% Group II patients. Five-year event-free survival (EFS) and overall survival (OS) were 77% and 89%, respectively. Survival rates were influenced by tumor size (EFS 92% and 56% for size < or = and > 5 cm, respectively) and local invasiveness, not by surgical margins. No metastatic relapses occurred in Group I < or = 5 cm patients, while the outcome was poor for T2B patients (EFS 41%) due to a high rate of metastatic relapse. Our study was unable to assess the role of adjuvant treatments in grossly-resected SS, but identified a subset of low-risk patients (IRS Group I, size < or = 5 cm), for which the omission of adjuvant chemotherapy could be suggested, and a subset of high-risk patients (T2B), who need treatment intensification.

Therapeutic potential of antibodies against FZD 10, a cell-surface protein, for synovial sarcomas

Genome-wide expression profiling revealed overexpression of the gene encoding frizzled homologue 10 (FZD 10), a cell-surface receptor for molecules in the Wnt pathway, as a potential contributor to synovial sarcomas (SS). Northern blotting and immunohistochemical staining confirmed that expression levels of FZD 10 were very high in nearly all SS tumors and cell lines examined but absent in most normal organs or in some cancers arising in other tissues. Treatment of human SS cells with small-interfering RNA (siRNA) to FZD 10 decreased the amount of its product and suppressed growth of SS cells. Moreover, a polyclonal antibody specifically recognizing the extracellular domain (ECD) of FZD 10 was markedly effective in mediating ADCC against FZD 10-overexpressing synovial sarcoma cells in vitro. Injection of the antibody into SS xenografts in nude mice attenuated tumor growth, and TUNEL assays revealed clusters of apoptotic cells in antibody-treated xenografts. Taken together, these findings suggest that a humanized antibody against FZD 10 might be a promising treatment for patients with tumors that overexpress FZD 10; minimal or no adverse reactions would be expected because FZD 10 protein is not abundant in vital organs.

Monophasic synovial sarcoma of the liver

We report a hepatic monophasic synovial sarcoma in a 60-year-old woman who presented with right upper quadrant pain subsequent to an intrahepatic bleed from a highly vascular tumor mass. Imaging studies showed a dominant tumor mass in the right hepatic lobe with multiple satellite nodules. A detailed physical examination and radiologic workup failed to reveal a primary tumor elsewhere. A right partial hepatectomy was performed with a preoperative differential diagnosis of angiosarcoma versus hepatocellular carcinoma. The morphologic, immunophenotypic, and cytogenetic findings (t(X;18)(p11.2;icq11.2)) were consistent with a monophasic synovial sarcoma. Postoperative clinical evaluation of the extremities and a positron emission tomographic scan performed 4 weeks after surgery showed no evidence of recurrent or metastatic disease. The patient was started on an aggressive 4-drug chemotherapy regimen, but died 3 months thereafter from widespread metastatic disease. No autopsy was performed. The presence of multiple lesions in the liver certainly suggests the possibility of metastatic disease. It would, however, be very unusual for a synovial sarcoma to present as an occult primary, and the negative radiologic workup 1 month after the partial hepatectomy also argues against this possibility. The clinical presentation, radiographic findings, and subsequent course in this patient was therefore most consistent with a primary monophasic synovial sarcoma of the liver.

Diagnosis and Management of Synovial Sarcoma

Synovial sarcoma is a unique tumor with substantial promise for biologically targeted therapy. Although it demonstrates moderate chemosensitivity, with approximately 50% response rates to ifosfamide- and doxorubicin-containing regimens, it has a diagnostic translocation and a potentially informative chimeric protein product. Although surgical management remains the cornerstone to effect local control, therapeutic advancements are unlikely to occur by continuing to include advanced cases of synovial sarcomas in trials with other soft tissue sarcomas. Rather, attention should be turned toward prospective molecular targets and development of novel agents to exploit them. Research should be directed at understanding the fusion protein of the X,18 translocation and further validating the role of overexpressed proteins in synovial sarcoma. Meanwhile, carefully designed clinical trials of these agents, with translational correlates, will provide in vivo data to complement the preclinical experience.

Clinical outcome of a novel photodynamic therapy technique using acridine orange for synovial sarcomas

Synovial sarcoma (SS) is one of common malignant soft-tissue tumors and is encountered most commonly in children and young adults. It frequently involves or invades major neurovascular structures and bones, and its local recurrence rate after simple resection has been reported to be as high as up to 80%. Because major nerves and vessels, as well as an adequate amount of bone, must be preserved to restore excellent limb function in cases of SS, a surgical technique entailing a low risk of local recurrence is needed. Based on the findings of recent experimental studies conducted by us using a mouse osteosarcoma model, we developed a novel therapeutic technique for SS, consisting of reduction surgery followed by photodynamic therapy using acridine orange (AO-PDT), with or without X-ray irradiation at 5 Gy. A preliminary study revealed that low-dose X-rays also excite AO like photons. After an initial study on cell cultures, this novel technique was applied to six cases of SS. A follow-up of the subjects to determine the clinical outcome revealed that none of the cases treated by AO-PDT, including the four cases treated by additional 5 Gy irradiation and the two cases not receiving any radiation, showed any evidence of recurrence or local/systemic complications during the follow-up period of 19-51 months after the surgery. Therefore, we believe that AO-PDT with 5 Gy irradiation may be an excellent novel therapeutic modality with reduction surgery to salvage excellent limb function in SS involving major nerves and vessels or bones.

Primary Synovial Sarcomas of the Mediastinum

A series of 15 cases of primary mediastinal neoplasms displaying histopathologic, immunohistochemical, and ultrastructural features of synovial sarcoma is presented. The patients' ages ranged from 3 to 83 years, with a male-to-female ratio of 2:1. Nine cases presented as anterior mediastinal masses with chest pain, shortness of breath, and pleural effusion, and 6 cases were in paravertebral location in the posterior mediastinum and presented with neck or back pain and pleural effusion. The tumors measured from 5 to 20 cm in greatest diameter and showed a tan white, soft to rubbery cut surface with areas of hemorrhage and necrosis and foci of gelatinous material. Four cases showed areas of cystic degeneration. In 7 cases, the tumors were well circumscribed; in 6 cases, the tumors grossly invaded the pleura, pericardium, heart, great vessels, chest wall, rib, and vertebra. Histologically, 5 cases displayed a biphasic growth pattern, with well-formed glandular elements admixed with a monotonous spindle cell population. Ten cases were exclusively composed of a monotonous atypical spindle cell proliferation. Immunohistochemical studies showed focal positivity of the tumor cells for cytokeratin and/or epithelial membrane antigen, and strong positivity for vimentin and bcl-2 in the spindle cells in all cases studied (10 of 10). Eight cases also showed focal positivity for CD99. Electron microscopic examination in 5 cases showed oval to spindle tumor cells with closely apposed cell membranes, abundant cytoplasmic intermediate filaments and rough endoplasmic reticulum, and immature desmosome-type cell junctions. Ten patients were treated by complete surgical excision and two by partial excision followed by radiation therapy. In 4 patients, the tumors were inoperable and treated with radiation therapy only. Clinical follow-up was available in 5 patients and showed local recurrence with metastases to lung, lymph nodes, and epidural space from 1 to 3 years in 4 cases and liver metastases and death due to tumor after 6 month in 1 case. Synovial sarcoma should be considered in the differential diagnosis of biphasic and monophasic spindle cell neoplasms of the mediastinum.

Synovial sarcoma in young people: background, prognostic factors, and therapeutic questions

Synovial sarcoma represents 5% to 10% of all soft tissue sarcomas, with an estimated total of 800 new cases annually in the United States. The median age is 30 years; males and females are almost equally affected. About 70% of cases occur in patients more than 20 years old. Young people less than 20 years of age are mainly affected in the second decade of life. The majority of the tumors occur in para-articular structures in the extremities, and most of them are localized at diagnosis. A recent meta-analysis of 219 patients younger than 21 years old treated by the University of Texas M. D. Anderson Cancer Center's Division of Pediatrics, St. Jude Children's Research Hospital, the German Cooperative Group, and Istituto Nazionale dei Tumori, Milan, found that, as in older people, tumor size larger than 5 cm, residual local tumor or metastases at diagnosis, and progressive or recurrent disease all portended a poor outcome. There are currently no randomized studies of therapy for patients with synovial sarcoma, but such are needed to provide answers to the following questions: Is adjuvant chemotherapy useful in preventing recurrence in patients without visible residual disease after apparently complete surgical removal of localized tumor? Should local radiation therapy be given to all patients who have had complete removal of the primary tumor with clear margins at the time of diagnosis?

Prospects for targeted therapy of synovial sarcoma

Synovial sarcoma is a distinct tumor with unique promise for targeted therapy. It has a diagnostic translocation and a potentially informative fusion protein. It has moderate chemosensitivity, with about 50% response rates to regimens containing ifosfamide and doxorubicin. Therapeutic advances are unlikely to occur by continuing to lump synovial sarcomas in trials with other soft tissue sarcomas and adjusting traditional agents; rather, attention should be turned toward prospective molecular targets and investigation or development of novel agents to exploit them. The SYT-SSX fusion protein that results from the X,18 translocation is an appealing target, as are the proteins overexpressed in synovial sarcoma: bcl-2, EGFR, and HER-2/neu.

Pediatric malignancies provide unique cancer therapy targets

PURPOSE OF REVIEW

Improving overall survival and reducing morbidity are major goals of childhood cancer research. This review explores an old idea that increased survival in childhood cancer can be achieved by inhibiting specific cancer targets. Specific therapeutic targeting would theoretically cause reduced morbidity as well as increased survival. Tumor-specific translocation-generated fusion proteins appear to be ideal tumor-specific therapeutic targets. This review will describe advances in aspects of target identification, potential for small molecule screening, and the evolution of clinical resistance to this new generation of pharmaceuticals.

RECENT FINDINGS

Advances in molecular biology have identified new protein targets along with increased understanding of the biologic role of these proteins. Ewing sarcoma family of tumors research has benefited from new target discovery and enhanced biologic understanding of the EWS-FLI1 fusion protein. Congenital (infantile) fibrosarcoma and cellular mesoblastic nephroma have been grouped based on the presence of a common translocation fusion protein, ETV6-NTRK3. Functional knowledge of ETV6-NTRK3 has advanced so that strategies for screening small molecule inhibitors can proceed. Patients with chronic myeloid leukemia have benefited from the discovery of the BCR-ABL kinase inhibitor imatinib mesylate (Gleevec), thus showing how a molecular therapeutic target can be inactivated for improved therapy. This review will describe challenges raised by clinical resistance to imatinib mesylate as a paradigm for how resistance might evolve in other disease models. This review also describes how patients with synovial sarcoma might benefit from future therapy directed towards the SYT-SSX family of fusion proteins.

SUMMARY

The increased utilization of small molecules to disrupt or inactivate tumor-specific molecular targets is rapidly evolving. The use of these small molecules to probe biology and treat disease is advancing towards a new generation of anticancer therapies.

Treatment effects in pediatric soft tissue and bone tumors: practical considerations for the pathologist

Dramatic improvements in survival for children with cancer have led to increased numbers of posttreatment pathologic specimens, particularly in bone and soft tissue sarcomas. Current therapeutic protocols in North America require specific pathologic classification and stratify patients based on clinical, biologic, and pathologic features. For osteosarcoma, the pathologic response to therapy predicts prognosis and modifies the treatment regimen. Ongoing studies aim to assess the response to therapy and outcome in other types of soft tissue and bone tumors. The pathologic evaluation of pretreatment and posttreatment specimens is critical for therapeutic decisions and prognostic assessment. A standardized approach to posttherapy pathologic specimens, with attention to appropriate use of ancillary tests, and assessment of clinical and biologic significance of therapy-induced pathologic changes has significance for patient management and treatment protocols.

Synovial sarcoma: A retrospective analysis of 271 patients of all ages treated at a single institution

BACKGROUND

The optimal treatment strategy for synovial sarcoma (SS) is subject to debate, and different strategies have been used for pediatric and adult patients. The current retrospective analysis examined a large group of patients of all ages who were treated at a single institution over a 30-year period.

METHODS

The study included 271 patients who ranged in age from 5 years to 87 years; 255 had localized disease, which was macroscopically resected in 215 cases and deemed unresectable at diagnosis in 40 cases. Chemotherapy was administered to 41% of patients, corresponding to 76% of patients age or 16 years and < 20% of older patients; 28% of patients with macroscopically resected disease received chemotherapy on an adjuvant basis.

RESULTS

The 5-year event-free survival rate for the study cohort as a whole was 37%, although this rate varied with age (66%, 40%, and 31% for patients age < or = 16 years, 17-30 years, and > 30 years, respectively). Chemotherapy was used more commonly for children than for adults. Among patients with surgically resected disease, the 5-year metastasis-free survival (MFS) rate was 60% for those who were treated with chemotherapy and 48% for those who were not; the benefit associated with chemotherapy use appeared to be greatest for patients age > or = 17 years who had tumors measuring > 5 cm (MFS, 47% [chemotherapy] vs. 27% [no chemotherapy]). In the subgroup of patients with measurable disease, the rate of tumor response to chemotherapy was approximately 48%.

CONCLUSIONS

Although the authors await more convincing proof of the efficacy of adjuvant chemotherapy in the treatment of adult soft tissue sarcoma, they recommend that patients with high-risk SS (tumor size > 5 cm) be the first to be considered for this type of treatment.

Primary Pulmonary Synovial Sarcoma: A Case Report and Review of Current Diagnostic and Therapeutic Standards

A 30-year-old female presented with hemoptysis, chest pain, and a rapidly enlarging pleural-based mass, and was found to have primary synovial sarcoma of the lung. Primary pulmonary sarcomas comprise <1% of all primary lung malignancies. They present clinically in young adults with cough, chest pain, shortness of breath, or hemoptysis, with a mass on x-ray and computerized tomography scan. Diagnosis is made by histology and immunohistochemistry. Histologic diagnosis has recently been supplemented by cytogenetic analysis, which offers important prognostic information. The mainstay of treatment remains complete surgical excision. Prognosis is poor, with an overall 5-year survival rate of 50%.

Synovial Sarcoma of the Kidney With Rhabdoid Features

We report 3 cases of synovial sarcoma with rhabdoid features, initially diagnosed as adult rhabdoid tumors. Two women (case nos. 1 and 2, 35 years and 27 years of age, respectively) and one man (case no. 3, 26 years of age) presented to their physicians with right flank pain. On physical examination, a poorly defined, firm, palpable mass was found in the upper right quadrant of the abdomen in all cases. Sonography and computed tomography revealed solid, cystic masses in the right kidneys that ranged in size from 8.5 to 20.0 cm. Right radical nephrectomies were performed in all patients. One patient died of disease, and the other two patients were alive and disease-free after chemotherapy and radiotherapy. Microscopic examination revealed that the tumors were composed mostly of rhabdoid cells with eccentrically located nuclei, prominent nucleoli, and eosinophilic cytoplasm. We also found areas of fasciculated spindle cells, sharply separated from or irregularly admixed with areas of rhabdoid cells. There was tumor necrosis, but no epithelial areas were seen. Hemangiopericytic vasculature was at least focally observed in all cases. The tumor cells were positive for CD99 and bcl-2 in all cases and for CD56 in two cases and negative for CD34 and smooth muscle actin in all cases. The cells in case no. 1 were focally positive for cytokeratin. To verify the possibility of synovial sarcoma with rhabdoid features, reverse transcriptase polymerase chain reaction using RNA extracted from frozen tissue in case no. 1 and formalin-fixed, paraffin-embedded tissue in case nos. 2 and 3 was performed. SYT-SSX2 transcripts were detected in all 3 cases. These cases indicate that synovial sarcoma of the kidney should be considered in the differential diagnosis of mesenchymal kidney tumors with prominent rhabdoid features. A subset of adult rhabdoid tumors may be a rhabdoid variant of synovial sarcoma, and molecular studies to detect SYT-SSX fusion transcripts are recommended for an accurate diagnosis.

Characteristics and outcome of children with primary soft tissue sarcomas of extremities

OBJECTIVES

To determine the characteristics and outcome or patients with primary soft tissue sarcomas of extremities in children.

MATERIAL AND METHODS

Thirty-six patients treated for soft tissues sarcomas were enrolled into the study. Features analysed: the incidence of soft tissues sarcoma of extremities, the time from first clinical symptoms to making the diagnosis, the primary site of tumour; histopathologic type of tumour, stage of disease, methods and results of the treatment.

RESULTS

The time From first symptoms to making the diagnosis was 5.4 months (mean). The site of the tumour was the femur in 6 patients, arm in 3, knee in 1. Histopathologic types: synovial sarcoma in 4 patients, malignant haemangiopericytoma in 2, rhabdomyosarcoma in 2, sarcoma myogenes in 1, primitive neuroectodermal tumour in l. Stage of disease: III deg. -- 8 patients, IV deg. -- 2. Patients underwent treatment according to the soft tissue sarcoma protocols. Results of treatment: first complete remission was observed in 7 patients; second complete remission in 1, one patient is on postoperative treatment. One patient died.

CONCLUSIONS

1. Combined treatment achieves full remission in the majority of patients with soft tissues sarcomas localized within the limbs. 2. In patients with large tumours (>5 cm) the treatment should to be started with inductive chemotherapy, and the surgery should be postponed. 3. Early excision of the tumour should be considered in cases of small tumours (< 5 cm), when resection with wide margin of healthy tissues is possible, without deteriorating the function of the limb or cosmetic damage.

Synovial Sarcoma Prognostic Factors and Patterns of Failure

From 1970 to 1999, 44 patients with synovial sarcoma were seen at the University of Iowa. Tumor size was > or = 5 cm in 24 (55%). Histologic classification was biphasic in 26 (59%) and monophasic in 18 (41%). Seven patients (16%) had distant metastasis at initial presentation. For the 37 nonmetastatic patients, local treatment consisted of wide local excision in 29 and amputation in 8; chemotherapy was administered to 10. For the 29 who underwent wide local excision, microscopic resection margins were negative in 18 and positive in 11; 19 received postoperative radiotherapy. The 5-, 10-, and 20-year overall survival rates for the nonmetastatic group were 65.6%, 45.5%, and 37.8%. On multivariate analysis using age as a continuous covariate, younger age (p = 0.028), biphasic histology (p = 0.014), and extremity sites treated with limb-sparing surgery (p = 0.001) were found to be predictors of a better overall survival. No local failures were found after 5 years from initial diagnosis. On multivariate analysis, tumor location at an extremity site was the only variable marginally found to have a better local control (p = 0.065). Of the 19 patients who developed distant metastasis, 5 (26%) failed >5 years and 2 (11%) failed >15 years of follow-up. Younger age, biphasic histology, and extremity sites were found to have a better survival outcome. Late distant relapses can occur with synovial sarcoma.

Synovial sarcoma: the importance of size and location for survival

A retrospective analysis was done on 135 consecutive patients with extremity and truncal synovial sarcomas seen at our institutions between 1961 and 1996. Ninety-nine patients (73%) presented with a newly diagnosed localized primary sarcoma, nine patients (7%) presented with a locally recurrent sarcoma previously treated at another institution, and 27 patients (20%) presented with metastatic disease. The median followup for surviving patients was 78 months (range, 20-420 months). The overall survival for patients with localized primary and locally recurrent synovial sarcoma was 51% at 10 years. Patients with localized synovial sarcomas less than 5 cm in longest diameter had a survival at 10 years of 88% compared with a 10-year survival of 38% and 8% for patients with sarcomas 5 to 10 cm and greater than 10 cm in longest diameter, respectively. Distal location (hands and feet) and histologic grade also were statistically significant predictors of patient survival for localized synovial sarcoma on univariate analysis. On multivariate analysis size greater than 10 cm and size 5 to 10 cm were associated with an 18-fold and a 3.1-fold increased risk of death compared with tumors smaller than 5 cm. Grade and location were not found to be independent predictors of survival on multivariate analysis. Primary tumor size and initial status at presentation were prognostic for survival and patients with synovial sarcomas larger than 5 cm or locally recurrent at presentation should be considered for more aggressive surgical and adjunctive radiotherapy or chemotherapy.

Synovial Sarcoma of the Soft Tissues

OBJECTIVE

This study assessed the prognostic value of computed tomography (CT) and magnetic resonance (MR) imaging features in synovial sarcoma of the soft tissues.

METHODS

CT and MR imaging studies were performed in 30 patients with pathologically confirmed synovial sarcoma of the soft tissues. CT and MR imaging findings obtained by 2 radiologists with agreement by consensus were compared for histopathologic features including tumor grade. Univariate analyses were conducted to clarify the impact of imaging findings on overall survival with a medium duration of 32 months. Multivariate analysis was estimated using a Cox proportional hazards model with the relative risk of each variable.

RESULTS

Statistically significant imaging findings favoring a diagnosis of high-grade tumor included proximal distribution (P < 0.01), large tumor size (>10 cm, P < 0.05), the absence of calcification (P < 0.05), tumor possessing cyst (P < 0.01), the presence of hemorrhage (P < 0.05), and the presence of triple signal pattern (P < 0.05). Univariate analysis showed that proximal distribution (P < 0.05), tumor size larger than 5 cm (P < 0.01), the absence of calcification (P < 0.01), the presence of hemorrhage (P < 0.05), and the presence of triple signal pattern (P < 0.05) had a significant association with the disease-free survival (DFS). Multiple logistic regression models revealed that tumor size larger than 10 cm had a significant impact on the DFS with relative risk of 18.8 (P < 0.05).

CONCLUSION

CT and MR imaging studies allow prognosis prediction in patients with synovial sarcoma of the soft tissues.

Synovial sarcoma in older patients: clinicopathological analysis of 32 cases with emphasis on unusual histological features

AIMS

To analyse the clinicopathological features of synovial sarcoma presenting in patients over 60 years of age, an uncommon subset which have not been specifically studied.

METHODS AND RESULTS

Thirty-two cases of primary synovial sarcoma in patients aged > or =60 years were retrieved from the authors' consultation files. These were analysed histologically and immunohistochemically and clinical follow-up was obtained in 26 cases (median duration 41 months). Mean age at diagnosis was 71.6 years (range 60-84) with 19 females and 13 males. Anatomical sites were lower limb (n = 13), upper limb (n = 5), lung/pleura (n = 5), trunk (n = 4), head/neck (n = 3), mediastinum (n = 1) and scrotum (n = 1). Histologically, 23 were monophasic and nine were biphasic; 14 were poorly differentiated, of which five showed focally marked pleomorphism. Unusual features in two cases each included organoid nodules, granular cell change, squamous metaplasia and papillary architecture. Ten patients developed local recurrence and 11 developed metastases, of whom seven died. Large tumour size, poorly differentiated morphology and high mitotic rate correlated with poor outcome.

CONCLUSIONS

Less than 10% of synovial sarcomas occur in patients over 60, in which age group this diagnosis is often not considered. Despite inevitable bias in consultation material, it seems that these cases, when compared with younger age groups, more often show poorly differentiated histology and more often develop at unusual locations.

Synovial sarcoma: a rare tumor of larynx

Synovial sarcoma is a soft tissue sarcoma of unknown histogenesis and occurs predominantly in the lower extremities of young adults. The head and neck is a relative rare location. There are about 10 cases with laryngeal localization in the literature. We present a 24 year-old male with an endolaryngeal mass. Incisional biopsy and the hemilaryngectomy material revealed a biphasic synovial sarcoma. One year later a local recurrence occurred. Tumor excision and neck dissection were performed. Radiotherapy was added. Six months later lung metastases was discovered on thoracic CT. The patient received chemotherapy for 6 courses. The metastases responded well to chemotherapy and the patient is now alive without tumor on radiological and clinical examination after 3.5 years of follow-up.