Prognostic factors that govern localized synovial sarcoma: a single institution retrospective study on 51 patients

The efficacy of re-excision after unplanned excision for synovial sarcoma

Background

This investigation studied the clinical features and outcomes of synovial sarcoma (SS) patients from a single institution.

Methods

A retrospective clinicopathologic study was conducted on 129 postoperative SS patients during 2003-2018. Kaplan-Meier curves and Cox proportional hazards regression (Cox) models were performed to determine the parameters associated with recurrence-free survival (RFS), metastasis-free survival (MFS), and cancer-specific survival (CSS) via univariate and multivariate analysis. The impact of unplanned excision (UE) and residual tumor in re-excision specimens was evaluated.

Results

The 3-year RFS, MFS and 5-year CSS were 72 %, 70 %, and 76 %, respectively. Independent factors associated with significantly inferior survival included older age, UE without re-excision, UE with residual tumors, high grade, and deep tumor for RFS, trunk-related tumor, UE without re-excision, UE with residual tumors, and deep tumor for MFS, UE with residual tumors, high grade, and deep tumor for CSS. Re-excision after UE was significantly associated with better RFS (P < 0.001). Residual tumors were remarkably correlated with inferior RFS (P = 0.0012), MFS (P = 0.0016), and CSS (P = 0.048), especially in patients at stage II (MFS: P < 0.001, CSS: P = 0.0014).

Conclusion

UE and residual tumors have a marked impact on the long-term survival of SS patients. Primary wide excision and re-excision is especially essential for patients at stage II.

Localised Synovial Sarcoma in Adolescents and Young Adults Versus Adults - Is There a Difference in Outcome?

AIMS

Synovial sarcomas are a rare subgroup of soft-tissue sarcoma arising in adolescents and young adults (AYA) and in adult patients. The objective of our analysis was to investigate the outcomes and potential differences of AYA versus adult patients with initially localised disease.

MATERIALS AND METHODS

In total, 51 patients (25 AYA and 26 adult) were identified and evaluated in this retrospective single centre analysis. Baseline characteristics, treatment and outcome were assessed.

RESULTS

The predominant subtype in both groups was monophasic synovial sarcoma (17 AYA and 21 adult) and the most common site was the extremities (14 and 19 patients) with deep tumour location in both groups (33 and 24 patients). More AYA patients had tumours >5 cm (13/25 patients) when compared with adults (10/26 patients, P = n.s.). Primary wide resection was carried out in 15 AYAs and in 18 adults. Postoperative radiation therapy was the only statistical difference between AYA (n = 19) and adult patients (n = 12; P = 0.029). Nineteen and 17 patients, respectively, received adjuvant chemotherapy with no evidence of disease after six cycles. Nine and 11 patients relapsed after initial therapy and the most common metastatic site was the lung (eight versus nine patients). Five-year overall survival rates were 85% and 75%. Female gender, tumour size ≤5 cm and absence of progressive disease showed a significant association with overall survival in AYA patients (P = 0.013, P = 0.04 and P < 0.001), whereas non-extremity tumours and progression after initial therapy were significant for worse overall survival in adult patients (P = 0.012 and P < 0.001). No difference in overall survival between AYA and adult patients was observed (P = 0.899).

CONCLUSIONS

AYA and adult patients showed no significant difference in terms of overall survival. Male gender, tumour size >5 cm and progressive disease were prognostic markers for worse outcome, whereas tumour location (non-extremity) and progression after initial therapy were markers for worse outcome in adult patients.

Soft Tissue Sarcomas: A 16-Year Experience of a Tertiary Referral Hospital in North Jordan

Background and Objectives: Sarcomas are rare malignant tumors of mesenchymal origin. Their low prevalence and histological heterogeneity make their diagnosis a challenging task. To the best of our knowledge, the epidemiology of soft tissue sarcomas (STSs) was not well studied in Jordan. This study thus aimed to determine STS epidemiologic trends at King Abdullah University Hospital (KAUH); a tertiary hospital that provides cancer healthcare for 70% of the population in Irbid Governorate, North Jordan. The findings of this study will provide a good reference point of the burden of STSs in Jordan and the Middle East region. Materials and Methods: All cases with confirmed STS diagnoses who attended KAUH from January 2003 until December 2018 were included in the initial analysis. Bone sarcomas, gastrointestinal stromal tumors and uterine sarcomas were not included in the study. Information collected from the pathology reports and electronic medical records was used to determine STS prevalence, incidence rate, age and gender distributions, histological types and anatomic location. Cases were reviewed by three pathologists with interest in soft tissue tumors. The findings were compared with literature. Results: In total, 157 STS cases were reported (1.9% of cancers diagnosed at KAUH during the 16-year study period). Crude annual incidence rate (IR) per 100,000 person-years ranged from 0.48 in 2015 to 1.83 in 2011 (average = 1.04). Age-standardized IR (ASR)(World WHO 2000–2025) was 1.37. Male:female ratio was 1.3:1. Median age was 39 years. Age ranged from <1 year to 90 years. Overall STS rates increased with age. The most common histological types were liposarcoma (19%), rhabdomyosarcoma (17%) and leiomyosarcoma (10%). The most common anatomic location was the extremity (40.1%), followed by the trunk (14.7%), then head and neck (10.8%). Conclusion: STSs are rare in North Jordan. A slight increase in their incidence was identified during the study period similar to global trends. The collection of relevant data on established risk factors along with a broader scale evaluation of the epidemiology of STS in the Middle East region is recommended to better evaluate disease burden and trends.

Clinical Significance and Risk Factors of Local Recurrence in Synovial Sarcoma: A Retrospective Analysis of 171 Cases

Objective: To investigate risk factors of local recurrence of synovial sarcoma and the impact of local recurrence on survival.

Methods: We retrospectively reviewed clinical data of patients with II to IIIB (AJCC8) synovial sarcoma who underwent surgery at our center between March 2005 and December 2016. Data relating clinicopathological factors, treatment and prognosis were collected. The impact of local recurrence on overall survival (OS), local recurrence-free survival (LRFS), and distant relapse-free survival (DRFS) were analyzed. The prognostic factors associated with local recurrence were also analyzed using Kaplan-Meier Curves and Cox regression analysis.

Results: A total of 171 patients were included in this analysis. After a median follow-up of 48 months, 66 patients (38.6%) experienced local recurrence. The 5-year OS, LRFS, and DRFS rates of patients with local recurrence were 37.6, 6.1, and 24.1%, respectively. Multivariate analysis showed that larger initial tumors, multiple recurrences, positive resection margins, marginal resection, and lack of adjuvant therapy were associated with higher local recurrence.

Conclusion: Local recurrence of synovial sarcoma is associated with distant metastasis and poor survival. Chemoradiation improves the prognosis of patients with local recurrence, in particular those for which recurrence occurs shortly after initial treatment.

Clinical Characteristics, Pathology and Outcome of 237 Patients With Synovial Sarcoma: Single Center Experience

BACKGROUND

Synovial sarcoma (SS) is a rare soft tissue sarcoma. Available data regarding survival outcomes of patients with SS still remains limited. In this study, a single center retrospective analysis was performed to investigate the clinical characteristics, pathology and survival outcomes in patients with SS in China.

METHODS

Patient data were systematically reviewed at the National Cancer Center from January 2015 to December 2020. The general information and treatment condition of patients were collected. Overall survival (OS) was evaluated using the Kaplan-Meier and Cox regression method.

RESULTS

A total of 237 consecutive patients were included in this study (follow-up cut-off date: December, 2020). The median age of patients involved was 35 years (ranging from 5 to 83 years) and the mean tumor diameter was 5.3 cm (ranging from .2 to 26.0 cm). The main findings of the immunohistochemical staining analyses were EMA (111/156) (71%), keratin (32/64) (50.0%), keratin (12/20) (60%), keratin (42/70) (60%), S-100 (18/160) (11%), BCL-2 (128/134) (96%), CD99 (137/148) (93%) and TLE1 (23/26) (88%). It was found that 109 patients (66%) were presented with monophasic subtype and 55 (34%) with biphasic subtype. A total of 137 patients were tested by FISH method and 119 patients (87%) demonstrated SS18 rearrangement, whereas 18 patients (13%) did not show SS18 rearrangement. Generally, it was found that the 3-year OS rate was 86% and the 3-year DFS was 55%. Results of univariate analysis revealed that age, tumor size, tumor site, radiotherapy and targeted therapy were significantly correlated with the overall survival (P < .05). Further, multivariate Cox regression analysis revealed that age, tumor size and radiotherapy were significantly associated with OS (P < .05).

CONCLUSIONS

In conclusion, this study shows that the outcomes of patients with SS significantly decrease with age and tumor size. It was evident that radiotherapy is an independent and positive prognostic factor for patients with SS. In addition, it was shown that the prognosis of SS varies with tumor location. For instance, primary tumors in lower extremities have a higher prognosis, whereas tumors located in thorax have a lower prognosis.

Magnetic resonance imaging findings of synovial sarcoma in children: location-dependent differences

BACKGROUND

While overall survival for children is greater than that for adults, synovial sarcoma remains an aggressive neoplasm with a potentially poor prognosis, and its magnetic resonance imaging (MRI) findings in children are not well described.

OBJECTIVE

We aimed to characterize the spectrum of MRI findings of synovial sarcoma in children with respect to anatomical location and outcome.

MATERIALS AND METHODS

Children with histologically confirmed synovial sarcoma and preoperative MRI performed within the past 11 years (2009-2020) were included. Two radiologists retrospectively reviewed each MRI to categorize location, signal characteristics and associated findings. Chi-square and Fisher exact tests were used to assess associations with locations and outcomes.

RESULTS

This study included 23 children (13 girls, 10 boys; mean age: 12.7±4.2 years) with 7 axial, 8 proximal and 8 distal appendicular lesions. Kappa ranged from 0.53 to 1. MRI findings differed significantly between locations with axial lesions measuring larger (P=0.01) and more likely to contain fluid levels (P=0.02), triple sign (P=0.02), inhomogeneous signal (T1-weighted images, P=0.003; T2-weighted images, P=0.02, contrast-enhanced images, P=0.03) with all lesions containing partially solid composition (P=0.03). At a median follow-up of 14 months (interquartile range: 7-33 months), 39% relapsed. Predictors of relapse (P<0.05) included metastasis at presentation, larger lesions, axial lesions and MRI findings of fluid level, T1-weighted hyperintensity, inhomogeneous signal (T1- and T2-weighted images) and poorly circumscribed margins.

CONCLUSION

A significant association was found between location and MRI findings in our cohort of children with synovial sarcoma. Axial lesions were more likely to be larger, appear heterogeneous and be associated with a worse outcome.

The effect of adjuvant therapies on long-term outcome for primary resected synovial sarcoma in a series of mainly children and adolescents

Background

The benefit of adjuvant therapy in synovial sarcoma (SS) treatment is under debate. Long-term follow-up data are missing.

Methods

SS patients treated in the consecutive trials CWS-81, CWS-86, CWS-91, CWS-96, CWS-2002-P, and the SoTiSaR-registry till 2013 were analyzed.

Results

Median age of 185 patients was 13.9 years (0.1–56)—with median follow-up of 7.4 years for 163 survivors. Most tumors (76%) were located in extremities. Size was < 3 cm in 58 (31%), 3–5 cm in 59 (32%), 5–10 cm in 42 (23%), and > 10 cm in 13 (7%) (13 missing). In 84 (45%) tumors, first excision was complete (R0 corresponding to IRS-I-group) and in 101 (55%) marginal (R1 corresponding to IRS-II-group). In a subsequent surgical intervention during chemotherapy, R0-status was accomplished in 23 additional IRS-II-group patients with secondary surgery. Radiotherapy was administered to 135 (73%), thereof 62 with R0-status and 67 R1-status (6 missing information). Adjuvant chemotherapy was administered to all but six patients. 5-year event-free (EFS) and overall survival (OS) was 82.9% ± 5.7 (95%CI) and 92.5% ± 3.9. Local and metastatic relapse-free survival was 91.3% ± 4.3 and 92.3% ± 4.1 at 5 years, respectively. In the multivariate analysis, tumor size and no chemotherapy were independently associated with EFS. Size and site were associated with OS. In a detailed analysis of local and metastatic events, tumor size was associated with an independent risk for developing metastases. No independent factor for suffering local recurrence could be identified.

Discussion

Omission of chemotherapy in a non-stratified way seems not justified. Size governs survival due to high linear association with risk of suffering metastatic recurrence in a granular classification.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00432-021-03614-6.

Efficacy of perioperative chemotherapy for synovial sarcoma: a retrospective analysis of a Nationwide database in Japan

BACKGROUND

Synovial sarcoma is an aggressive but chemosensitive soft-tissue tumor. We retrospectively analyzed the efficacy of perioperative chemotherapy for synovial sarcoma with data from the nationwide database, Bone and Soft Tissue Tumor Registry in Japan.

METHODS

This study included 316 patients diagnosed with synovial sarcoma between 2006 and 2012. Oncologic outcomes were analyzed using a Cox-hazard regression model. Moreover, the effects of perioperative chemotherapy on outcomes were evaluated using a matched-pair analysis. The oncologic outcomes of patients who did or did not receive chemotherapy were compared (cx + and cx-).

RESULTS

Multivariate analysis revealed significant correlations of age (over 40, hazard ratio [HR] = 0.61, p = 0.043), margin status (marginal resection, HR = 0.18, p < 0.001 and intralesional resection, HR = 0.30, p = 0.013 versus wide resection) with overall survival; surgical margin type (marginal resection, HR = 0.14, p = 0.001 and intralesional resection, HR = 0.09, p = 0.035 versus wide resection) with local recurrence; and postoperative local recurrence (HR = 0.30, p = 0.027) and surgical margin (marginal resection, HR = 0.31, p = 0.023 versus wide resection) with distant relapse-free survival. Before propensity score matching, perioperative chemotherapy was mainly administered for young patients and patients with deeper tumor locations, larger tumors, more advanced-stage disease, and trunk location. The 3-year overall survival, local control, and distant relapse-free survival rates were 79.8%/89.3% (HR = 0.64, p = 0.114), 89.6%/93.0% (HR = 0.37, p = 0.171) and 71.4%/84.5% (HR = 0.60, p = 0.089) in the cx+/cx- groups, respectively. After propensity score matching, 152 patients were selected such that the patient demographics were nearly identical in both groups. The 3-year overall survival, local control, and distant relapse-free survival rates were 71.5%/86.0% (HR = 0.48, p = 0.055), 92.5%/93.3% (HR = 0.51, p = 0.436) and 68.4%/83.9% (HR = 0.47, p = 0.046) in the cx+/cx- groups, respectively.

CONCLUSION

This large-sample study indicated that the margin status and postoperative disease control were associated directly or indirectly with improved oncologic outcomes. However, the efficacy of perioperative chemotherapy for survival outcomes in synovial sarcoma patients was not proven in this Japanese database analysis.

The value of multidisciplinary team (MDT) management in the diagnosis and treatment of primary intrathoracic synovial sarcomas: a single-center experience

Background

Synovial sarcoma (SS) is a rare malignant soft tissue tumor. Primary intrathoracic SS is extremely rare, with limited diagnosis and treatment experiences. The aim of our study was to retrospectively study the clinicopathological characteristics, treatment and prognosis of primary intrathoracic SS and the impact of multidisciplinary team (MDT) management in diagnosis and treatment on patient prognosis.

Methods

The clinical and pathological characteristics, treatment, survival and prognosis of patients with primary intrathoracic SS admitted to the National Cancer Center from January 1999 to December 2018, as well as MDT intervention during diagnosis and treatment, were retrospectively analyzed.

Results

Thirteen patients were enrolled, including 7 (53.8%) males and 6 (46.3%) females, with primary intrathoracic SS in the lung (8/13, 61.5%), mediastinum (4/13, 30.8%) and pleura (1/13, 7.7%) as confirmed by morphological observation, immunohistochemical (IHC) staining and fluorescence in situ hybridization (FISH). Overall, 10/13 (76.9%) patients underwent surgery, and 6/10 (60.0%) received postoperative adjuvant therapy. Only 23.1% of patients received nonsurgical therapy. The MDT discussed and managed seven patients before and/or after surgery and one patient who did not undergo surgery. The estimated 3- and 5-year overall survival (OS) rates were 50.0% and 30.0%, respectively. Patients who were managed by an MDT had a longer median OS time than those who were not (46.0 vs. 18.0 months). Age (P=0.018), tumor location (P=0.029), and Ki-67 (P=0.020) were found to be significantly related to OS.

Conclusions

Monophasic morphology and fusion gene characteristics are the main features for the diagnosis of primary intrathoracic SS. MDT management can help obtain accurate diagnoses and provide reasonable therapeutic options.

Multimodal Risk-Adapted Treatment in Surgical Patients With Synovial Sarcoma: A Preoperative Nomogram-Guided Adjuvant Treatment Strategy

Background: Synovial sarcoma is characterized by heterogeneous clinical manifestations, making it difficult to evaluate individual patients' prognoses and design personal treatment schemes. We established an effective preoperative nomogram to predict cancer-specific survival (CSS) and present a risk-adapted adjuvant treatment strategy in surgical patients with synovial sarcoma. Methods: This retrospective study included patients from the Surveillance, Epidemiology, and End Results (SEER) database who were diagnosed with synovial sarcoma between 1996 and 2015. The patients were randomly divided into training and validation groups. The predictors were selected using univariate and multivariate Cox hazards models. The nomogram performance was verified for its discriminatory ability and calibration. We further stratified the patients into different risk groups according to the nomogram scores and compared the efficacy of chemotherapy, radiotherapy, and combination of radiotherapy and chemotherapy. Results: There were 915 patients enrolled in our study, with 874 patients either alive or dead due to synovial sarcoma. We established a nomogram to predict 5-year CSS based on independent factors, including sex, age, grade, tumor size, location, and extent (all p < 0.05). Our model showed a consistently good discriminatory ability and calibration for predicting 5-year CSS in both the training (c-index = 0.78, 95% CI 0.75-0.81) and validation (c-index = 0.73, 95% CI 0.68-0.78). Based on their nomogram scores, we divided patients into 5 groups. Compared to patients without adjuvant treatment, nomogram I patients with adjuvant treatment had no improvements in 5-year CSS (100.0% vs. 100.0%), nomogram II patients had higher 5-year CSS with radiotherapy or chemotherapy (92.9% vs. 72.2%, p = 0.015), nomogram III patients had higher 5-year CSS with combination of chemotherapy and radiotherapy (70.1% vs. 47.2%, p = 0.004), nomogram IV patients had higher 5-year CSS with radiotherapy (41.3% vs. 15.6%, p = 0.015), and nomogram V patients had no improvements in 5-year CSS rates with adjuvant treatment (28.9% vs. 16.9%, p = 0.18). Conclusion: The nomogram showed a satisfactory discriminatory ability and calibration for predicting 5-year CSS in synovial sarcoma patients. Based on this nomogram, we stratified synovial sarcoma patients according to risk levels, which enabled us to provide a useful grouping scheme that can inform multimodal risk-adapted treatment in synovial sarcoma.

Surgical excision and not chemotherapy is the most powerful modality in treating synovial sarcoma: the UK's North East experience

BACKGROUND AND PURPOSE

We reviewed our experience of synovial sarcoma to identify factors predictive of local recurrence and overall survival, the impact of chemotherapy and outcomes after surgical excision alone.

MATERIALS AND METHODS

81 patients were treated between 1997 and 2014 of mean age 39 years (8-78). Tumours were in the extremity in 55 (67%). 9 patients presented with metastases and 10 with unresectable disease. Mean follow-up was 3.7 years (SD 3.8). Treatment groups were palliative, surgery only, surgery and radiotherapy, or surgery with chemotherapy (with or without radiotherapy).

RESULTS

Local recurrence-free survival (LRFS) was 73% at 5 years, and 68% at 10 and 15 years. In multivariate analysis, positive surgical margins were an independent predictor of LRFS. Overall survival (OS) was 50% at 5 years for all patients, and 62% at 5 years for those treated with curative intent. Larger tumour size and non-extremity locations were predictors of poorer OS. Patients who had chemotherapy did not have significantly better OS or LRS than others.

INTERPRETATION

These results show that where feasible, curative resection should not be delayed for chemotherapy. Treatment with surgery only can be associated with good outcomes in selected patients with smaller extremity tumours; although our series is small.

Beclin1 overexpression suppresses tumor cell proliferation and survival via an autophagy‑dependent pathway in human synovial sarcoma cells

Beclin1 is an important autophagy‑related prot-ein, which is involved in both autophagy and apoptosis. In recent years, the antitumor effect of Beclin1 has received increased attention. In the present study, we established a stable Beclin1‑overexpressing cell line with SW982 human synovial sarcoma cells. We found that Beclin1 overexpression decreased the cell viability, inhibited proliferation and induced apoptosis in SW982 cells. The expression levels of Bcl‑2 and PCNA were decreased, while the levels of cleaved‑caspase‑3 and cleaved‑PARP were increased. Beclin1 is closely related with autophagy, thus the autophagy‑related markers LC3 and p62 were detected by western blot analysis, and transmission electron microscopy was used to observe autophagosomes. The results showed that the expression level of LC3II was increased and that of p62 was decreased. Moreover, many double membrane‑enclosed autophagosomes were found in cells with Beclin1 overexpression, which indicated that the autophagic activity was enhanced. To explore the effect of autophagy on the viability of SW982 cells, Atg5 was knocked down using siRNA to inhibit the autophagic activity. We found that autophagy contributed to the decrease in cell viability. Knockdown of Atg5 increased the viability and decreased the apoptotic rate of SW982 cells with Beclin1 overexpression. The expression level of Bcl‑2 was increased, while the expression levels of cleaved‑caspase‑3 and cleaved‑PARP were decreased. We also found that the Akt/Bcl‑2/caspase‑9 pathway was involved. The phosphorylation of AKT was positively correlated with cell viability. The cleavage of caspase‑9 was increased by Beclin1 overexpression and decreased by inhibition of autophagy. Altogether, our results suggested that both autophagy and apoptosis contributed to the antitumor effect of Beclin1 in SW982 cells.

Biphasic axillary synovial sarcoma diagnosed by preoperative fine-needle aspiration cytology

Synovial sarcoma (SS) is a soft-tissue sarcoma which usually occurs in lower extremities. Less than 20 cases of SS located in shoulder or axillary region have been reported, and these studies describe histopathological features. We report a case of axillary SS diagnosed by fine-needle aspiration cytology, immunocytochemistry, and molecular techniques performed on cytology smears. A 48-year-old woman presented with a palpable and well-defined axillary mass which measured 4 cm. On-site smears showed high cellularity with spindle cells, and a mesenchymal tumor was suspected. Definitive cytological analysis showed cells with ovoid- or comma-shaped nuclei arranged in loose sheets and fascicles, associated with naked nuclei and isolated cells. Mitotic count was 2 mitoses/HPF. Immunocytochemical studies showed vimentin and focal CK AE1-AE3 positivity. A PCR was performed and the specific translocation t(X;18) was detected. The lesion was excised and the diagnosis of biphasic SS was confirmed. The identification of SS on cytology specimens is difficult and differential diagnosis is broad. Complementary studies are necessary and they can be performed on FNA smears or cell blocks.

[Synovial sarcoma in children and adolescents]

Synovial sarcoma (SS) is a rare high-grade malignant mesenchymal tumor affecting children, adolescents, and young adults. Cytogenetically, more than 90% of SS is characterized by the t(X;18)(p11.2;q11.2), translocation resulting in two chimeric fusion genes SYT-SSX1 and SYT-SSX2, confirming histological diagnosis. Pediatric SS arises most often in soft tissues of the extremities (66% of cases), and is a localized tumor without spreading to regional lymph nodes (96% of cases) nor to metastatic sites (94% of cases). Although clinical and radiologic presentation, histologic analysis and tumor biology appear similar in pediatric and adolescent SS, outcome seems better in children than in adolescents, respectively 84% vs 60% of 5years overall survival (OS). If complete resection is the gold standard in SS, other therapeutic modalities differ between pediatric and adult populations, considering SS as an intermediate chemosensitive tumor more frequently by pediatric oncologists. Prognostic factors evaluation (tumor size, site of primary and IRS group) is necessary to establish optimal treatment strategies, with multimodal therapeutic approach in children and adolescents. Thus, recent results about the European prospective EpSSG NRSTS 05 study for children and adolescent patients with localized SS showed a 5years OS >90%. Moreover, recent somatic genetic data about SS open the debate on an appropriate strategy based and stratified on tumor genomic. Multinational prospective pediatric, adolescent and young adult study is necessary to improve optimal and appropriate approach in this rare tumor.

Age as an independent prognostic factor for survival of localised synovial sarcoma patients

Background:

We performed a retrospective nationwide study to explore age as a prognostic factor in synovial sarcoma patients.

Methods:

Data on 613 synovial sarcoma patients were obtained from the Netherlands Cancer Registry. The prognostic relevance of age groups (children, adolescent and young adults (AYAs), adults, and elderly) was estimated by Kaplan–Meier survival curves and multivariable Cox-proportional hazards modelling.

Results:

A total of 461 patients had localised disease at diagnosis. The 5-year overall survival (OS) was 89.3±4.6%, 73.0±3.8%, 54.7±3.6%, and 43.0±7.0% in children (n=54), AYAs (n=148), adults (n=204), and elderly (n=55), respectively. Treatment modalities had no significant effect on survival in the univariable analysis. Multivariable analysis identified age at diagnosis, tumour localisation, and tumour size as significant factors affecting OS. Both tumour localisation and size were equally distributed over the age groups.

Conclusions:

We show that outcome of synovial sarcoma patients significantly decreases with age regardless of primary tumour site, size, and treatment.

Synovial sarcoma: defining features and diagnostic evolution

Synovial sarcoma (SS) is a malignant mesenchymal neoplasm with variable epithelial differentiation, with a propensity to occur in young adults and which can arise at almost any site. It is generally viewed and treated as a high-grade sarcoma. As one of the first sarcomas to be defined by the presence of a specific chromosomal translocation leading to the production of the SS18-SSX fusion oncogene, it is perhaps the archetypal "translocation-associated sarcoma," and its translocation remains unique to this tumor type. Synovial sarcoma has a variety of morphologic patterns, but its chief forms are the classic biphasic pattern, of glandular or solid epithelial structures with monomorphic spindle cells and the monophasic pattern, of fascicles of spindle cells with only immunohistochemical or ultrastructural evidence of epithelial differentiation. However, there is significant morphologic heterogeneity and overlap with a variety of other neoplasms, which can cause diagnostic challenge, particularly as the immunoprofile is varied, SS18-SSX is not detected in 100% of SSs, and they may occur at unusual sites. Correct diagnosis is clinically important, due to the relative chemosensitivity of SS in relation to other sarcomas, for prognostication and because of the potential for treatment with specific targeted therapies in the near future. We review SS, with emphasis on the diagnostic spectrum, recent immunohistochemical and genetic findings, and the differential diagnosis.