Chemotherapy is associated with improved survival in adult patients with primary extremity synovial sarcoma

Treatment at relapse for synovial sarcoma of children and adolescents: A multi-institutional European retrospective analysis

PURPOSE

Though the prognosis for pediatric patients with localised synovial sarcoma (SS) is generally good, the chances of being cured after relapse are limited. This study describes a retrospective multi-institutional series of relapsing SS patients treated at six selected European referral centers for pediatric sarcoma.

PATIENTS AND METHODS

The study included 41 patients <21 years with relapsing SS, treated between 2002 and 2022. The analysis included patient's characteristics at first diagnosis, first-line treatments, clinical findings at relapse, and second-line treatment modalities.

RESULTS

The first relapse occurred within 3-132 months (median 18 months) after first diagnosis and was local in 34%, metastatic in 54%, and both in 12%. Treatment at first relapse included surgery in 56% of cases, radiotherapy in 34%, and systemic therapy in 88%. In all, 36 patients received second-line medical treatment, that was chemotherapy in 32 cases (with 10 different regimens) and targeted therapy in four. No patient was included in an early-phase clinical trial as second-line therapy-line therapy. Overall response rate was 42%. Median event-free survival (EFS) was 12 months, postrelapse 5-year EFS was 15.8%. Median overall survival (OS) was 30 months, postrelapse 5-year OS was 22.2%. At the Cox's multivariable regression analysis, OS was significantly associated with time and type of relapse.

CONCLUSION

Pediatric patients with relapsed SS have a poor prognosis and generally receive an individualized approach, due to the lack of a uniform standardized approach. New comprehensive strategies are needed to improve the knowledge on the biologic landscape of SS and develop tailored prospective clinical trials.

Clinicopathological Profile and Survival Outcomes in Patients with Localised Extremity Synovial Sarcomas

AIMS

Synovial sarcoma is a rare but aggressive variant of soft-tissue sarcoma. Literature is sparse and reported mostly from the West. We analysed the clinical profiles and prognostic factors of extremity synovial sarcoma patients in order to study their clinical journey.

MATERIALS AND METHODS

This was a retrospective analysis. All patients with extremity synovial sarcoma treated between 1992 and 2020 were included. Patients with metastases at presentation were excluded. A descriptive analysis of demographic and clinicopathological features of patients undergoing limb salvage surgery (LSS) or amputation was carried out. Overall survival and disease-free survival were calculated for the entire cohort as well as for the LSS and amputation groups. Factors prognostic for survival were identified.

RESULTS

In total, 157 patients had localised extremity synovial sarcoma. Predominantly, young adults (median 31 years) and males (61%) were affected. Over 70% of patients presented after recurrence or unplanned surgeries. Sixty-seven per cent of tumours were >5 cm, 69% were deep and 23% involved bone. The limb salvage rate was 64%. In the LSS group, adjuvant radiotherapy and chemotherapy were given to 72% and 68% of patients, respectively. In the amputation group, 72% of patients received adjuvant chemotherapy. In a median follow-up of 59 months, 39.4% of patients had recurrences, the majority (61.2%) were systemic. Five-year overall survival and disease-free survival were 53.4% and 49.8%, respectively. Overall survival was 63.9% and 29.7% in the LSS and amputation groups, respectively. On multivariate analysis, tumour size, depth, omission of radiotherapy and bone invasion were found to be the adverse prognostic factors.

CONCLUSION

This is one of the largest studies on extremity synovial sarcoma. Mostly males and young adults were affected. The limb salvage rate was 64%, despite most being referred after unplanned surgery. Almost 70% of patients received radiotherapy and chemotherapy. Overall survival was inferior in the amputation group. Tumour size >5 cm, depth and bone invasion were negative, whereas adjuvant radiotherapy was a positive prognostic factor for survival. Chemotherapy had no impact on survival.

Team Approach: Extremity Soft Tissue Sarcoma

» Synovial sarcoma is a soft tissue sarcoma that most commonly presents in the extremity in a periarticular location.» As the history and physical examination of patients with synovial sarcoma can overlap considerably with those of patients with non-oncologic orthopedic conditions, it is important that orthopedic surgeons maintain a high level of suspicion when caring for patients with extremity masses.» Soft tissue sarcomas are best treated using a team approach. Early recognition and referral to a multidisciplinary sarcoma team are crucial to ensure the best clinical outcome for the patient.

Treatment at Relapse for Synovial Sarcoma of Children, Adolescents and Young Adults: From the State of Art to Future Clinical Perspectives

While the overall prognosis is generally quite satisfactory in children, adolescents and young adults with localised synovial sarcoma at first diagnosis, the outcome remains poor for patients after relapse. Conversely to the front-line standardised treatment options, patients with relapse generally have an individualised approach and to date, there is still a lack of consensus regarding standard treatment approaches. Studies on relapsed synovial sarcoma were able to identify some prognostic variables that influence post-relapse survival, in order to plan risk-adapted salvage protocols. Treatment proposals must consider previous first-line treatments, potential toxicities, and the possibility of achieving an adequate local treatment by new surgery and/or re-irradiation. Effective second-line drug therapies are urgently needed. Notably, experimental treatments such as adoptive engineered TCR-T cell immunotherapy seem promising in adults and are currently under validation also in paediatric patients.

Organoid models derived from patients with malignant phyllodes tumor of the breast

PURPOSE

Phyllodes tumor of the breast is a kind of rare neoplasm, which accounts for less than 1% of all breast tumors. Malignant phyllodes tumor (MPT) is the highest risk subtype of phyllodes tumor, and is characterized by the tendency of local recurrence and distant metastasis. The prediction of prognosis and the individual therapy for MPT is still challenging. It's urgent to develop a new reliable in vitro preclinical model in order to understand this disease better and to explore appropriate anticancer drugs for individual patients.

METHODS

Two surgically resected MPT specimens were processed for organoid establishment. MPT organoids were subsequently subjected to H&E staining, immunohistochemical analysis and drug screening, respectively.

RESULTS

We successfully established two organoid lines from different patients with MPT. The MPT organoids can well retain the histological features and capture the marker expression in original tumor tissues, including p63, vimentin, Bcl-2, CD34, c-Kit, and Ki-67, even after a long-term culture. The dose titration tests of eight typical chemotherapeutic drugs (paclitaxel, docetaxel, vincristine, doxorubicin, cisplatin, gemcitabine, cyclophosphamide, ifosfamide) on the two MPT organoid lines showed patient-specific drug responses and varying IC₅₀ values. Of all the drugs, doxorubicin and gemcitabine showed the best anti-tumor effect on the two organoid lines.

CONCLUSION

Organoids derived from MPT may be a novel preclinical model for testing personalized therapies for patients with MPT.

Spindle cell thymoma and its histological mimickers

Spindle cell thymomas are the most common spindle cell neoplasms of the anterior mediastinum. These tumors belong to the group of thymic epithelial neoplasms and are known for their wide histomorphologic spectrum. This histological heterogeneity is the reason why unequivocal diagnosis can be challenging, especially when dealing with small biopsy material. Conversely, less conventional patterns of the tumor may also pose significant diagnostic problems in resected material and the differential diagnosis often includes other spindle cell neoplasms that are known to arise in the mediastinal cavity. These can be of variable origin and may share overlapping pathological features with spindle cell thymoma. Since spindle cell thymomas are tumors that primarily affect the adult population and predominantly arise from the thymic gland in the anterior mediastinum, this review will focus on the differential diagnosis with other spindle cell neoplasms that share similar demographic characteristics and, for the most part, originate from the anterior mediastinal compartment. These include other epithelial spindle cell tumors of thymic origin (sarcomatoid thymic carcinoma and spindle cell carcinoid tumor), mesenchymal neoplasms [solitary fibrous tumor (SFT), synovial sarcoma, and dedifferentiated liposarcoma] and various other tumors with spindle cell morphology, that may occasionally involve the anterior mediastinum. The clinical, pathological, immunohistochemical and molecular hallmarks of these lesions will be discussed and useful tips for the differential diagnosis with spindle cell thymoma will be provided.

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.

Emerging targeted and cellular therapies in the treatment of advanced and metastatic synovial sarcoma

Synovial sarcoma is a soft tissue sarcoma accounting for approximately 1,000 cases per year in the United States. Currently, standard treatment of advanced and metastatic synovial sarcoma is anthracycline-based chemotherapy. While advanced synovial sarcoma is more responsive to chemotherapy compared to other soft tissue sarcomas, survival rates are poor, with a median survival time of less than 18 months. Enhanced understanding of tumor antigen expression and molecular mechanisms behind synovial sarcoma provide potential targets for treatment. Adoptive Cell Transfer using engineered T-cell receptors is in clinical trials for treatment of synovial sarcoma, specifically targeting New York esophageal squamous cell carcinoma-1 (NY-ESO-1), preferentially expressed antigen in melanoma (PRAME), and melanoma antigen-A4 (MAGE-A4). In this review, we explore the opportunities and challenges of these treatments. We also describe artificial adjuvant vector cells (aAVCs) and BRD9 inhibitors, two additional potential targets for treatment of advanced synovial sarcoma. This review demonstrates the progress that has been made in treatment of synovial sarcoma and highlights the future study and qualification needed to implement these technologies as standard of care.

Clinical analysis of multimodal treatment for localized synovial sarcoma: A multicenter retrospective study

INTRODUCTION

Several prognostic factors for survival in synovial sarcoma have been proposed, but the role of adjuvant chemotherapy and radiotherapy is a matter of debate. The study aim was to clarify the effect of high-dose ifosfamide-containing chemotherapy and adjuvant radiotherapy for patients with localized synovial sarcoma.

MATERIALS AND METHODS

Five tertiary musculoskeletal oncology hospitals participated in this retrospective study. The records of the patient diagnosed with synovial sarcoma without metastasis at diagnosis from 1990 to 2011 have been collected and reviewed. Overall, distant failure-free, and local failure-free survivals were calculated, and prognostic factors for each survival were evaluated by performing univariate and multivariate analyses.

RESULTS

A total of 162 patients were enrolled in this study with a median follow-up period of 67 months (range, 5-267 months) for all surviving patients. The 5-year overall, distant failure-free, and local failure-free survival rates were 79.7%, 66.3%, and 98.4%, respectively. Univariate analyses demonstrated that high-dose ifosfamide-containing chemotherapy was significantly associated with better overall (p = 0.014) and distant failure-free survival (p = 0.0043) than that of low-dose or no ifosfamide-containing chemotherapy if we analyzed only patients with tumors >5 cm in size. Addition of radiotherapy was not a significant prognostic factor for overall survival in the univariate and multivariate analyses, but it did improve the overall survival of the patients with R1 resection (p = 0.053).

CONCLUSION

Patients with localized synovial sarcoma >5 cm in size had better overall and distant failure-free survival after receiving adjuvant chemotherapy containing high-dose ifosfamide comparing to low-dose or no ifosfamide-containing chemotherapy. The addition of adjuvant radiotherapy was beneficial for the patients who received R1 resection. Alternatively, adjuvant radiotherapy could be avoided for patients who achieved an R0 margin.

Presurgical Perspective and Posttreatment Evaluation of Soft Tissue Tumors of the Ankle and Foot in Adults

This article discusses soft tissue tumors of the ankle and foot region in adults, including tumors of the joints, and also briefly addresses tumor-simulating lesions. We offer general recommendations and describe specific aspects of common entities in that region, such as typical imaging appearance, therapeutic strategies, and posttherapeutic considerations. Focal masses and diffuse swelling are common in the foot and ankle region; most of them are non-neoplastic. Some of the tumors, such as plantar fibromatosis, tenosynovial giant cell tumor, synovial chondromatosis, or schwannoma, have a very typical appearance on magnetic resonance imaging. Sarcomas are rare among true soft tissue tumors; however, they can be small and well demarcated, may grow slowly, and are often misinterpreted as benign. This is especially true for synovial sarcoma, one of the most common sarcomas in this region. Densely packed tissues in the foot and ankle may hamper determining the tissue of origin. Adherence to diagnostic guidelines and cooperation with tumor centers is crucial including for posttherapeutic surveillance. We also describe typical posttherapeutic changes and complications after surgery, radiation therapy, and chemotherapy, as well as parameters for the detection and exclusion of recurrence of soft tissue tumors of the ankle and foot.

Characterisation of a Novel Cell Line (ICR-SS-1) Established from a Patient-Derived Xenograft of Synovial Sarcoma

Synovial sarcoma is a rare translocation-driven cancer with poor survival outcomes, particularly in the advanced setting. Previous synovial sarcoma preclinical studies have relied on a small panel of cell lines which suffer from the limitation of genomic and phenotypic drift as a result of being grown in culture for decades. Patient-derived xenografts (PDX) are a valuable tool for preclinical research as they retain many histopathological features of their originating human tumour; however, this approach is expensive, slow, and resource intensive, which hinders their utility in large-scale functional genomic and drug screens. To address some of these limitations, in this study, we have established and characterised a novel synovial sarcoma cell line, ICR-SS-1, which is derived from a PDX model and is amenable to high-throughput drug screens. We show that ICR-SS-1 grows readily in culture, retains the pathognomonic SS18::SSX1 fusion gene, and recapitulates the molecular features of human synovial sarcoma tumours as shown by proteomic profiling. Comparative analysis of drug response profiles with two other established synovial sarcoma cell lines (SYO-1 and HS-SY-II) finds that ICR-SS-1 harbours intrinsic resistance to doxorubicin and is sensitive to targeted inhibition of several oncogenic pathways including the PI3K-mTOR pathway. Collectively, our studies show that the ICR-SS-1 cell line model may be a valuable preclinical tool for studying the biology of anthracycline-resistant synovial sarcoma and identifying new salvage therapies following failure of doxorubicin.

The Role of Surgery for Primary Pulmonary Synovial Sarcoma: A Population-Based Study

INTRODUCTION

The rarity of primary pulmonary synovial sarcoma (PPSS) and the lack of prospective clinical trials resulted in poorly understood treatment modality and clinical outcomes. This study aimed to better understand PPSS based on patients from the Surveillance, Epidemiology, and End Results database.

MATERIALS AND METHODS

Clinical and survival data of PPSS patients who were diagnosed during 1989 through 2016 and retrieved from the Surveillance, Epidemiology, and End Results database were studied. Kaplan-Meier analyses and Cox proportional hazards model were applied to evaluate the overall survival (OS) and disease-specific survival (DSS) of PPSS patients.

RESULTS

A total of 122 patients with PPSS were included (median age: 50 y). PPSS accounted for 4.5% (122/2741) of total primary synovial sarcoma. Most of the patients were diagnosed as poor or undifferentiated grade (52.0% and 34.0%). Cancer-directed surgery was performed for 74.4% of PPSS patients and 28.2% of patients received radiotherapy. The 1-year, 3-year, 5-year, and 10-year OS rates of PPSS patients were 75.4%, 50.8%, 41.8%, and 39.3%, respectively. Cancer-directed surgery was shown to improve the survival of PPSS patients with localized or regional stage (P < 0.05), yet surgical resection did not prolong the OS and DSS of patients with distant stage (P > 0.1). Postoperational radiotherapy was associated with shortened survival time (P < 0.05). PPSS patients who received lobectomy had statistically prolonged OS and DSS than those with pneumonectomy (P < 0.001).

CONCLUSIONS

PPSS is a rare and special subtype of synovial sarcoma. Treatment with lobectomy or sublobar resection alone may contribute to a superior prognosis compared with other managements.

Oncostatin M Receptor as a Therapeutic Target for Radioimmune Therapy in Synovial Sarcoma

Synovial sarcoma (SS) is a pediatric muscle cancer that primarily affects adolescents and young adults and has few treatment options. Complicating the treatment of synovial sarcoma is the low mutational burden of SS. Inflammatory pathways have been identified as being upregulated in some SS, leading to the discovery of upregulated oncostatin M receptor (OSMR). It was found that OSMR is upregulated in SS by RNAseq analysis and quantitative PCR, highlighting its potential in the treatment of SS. Also, OSMR is upregulated in mouse models for synovial sarcoma as demonstrated by western blot and immunohistochemistry, and the protein is present in both primary and metastatic sites of disease. Using a radioimmune therapy drug model, targeted therapy was synthesized for use in OSMR expressing SS and it was demonstrated that this drug is stable, while capable of efficient OSMR binding and isotope capture. Finally, this antibody conjugate exhibited ideal pharmacokinetics and targeted sites of disease in our mouse model and was taken up in both primary and metastatic diseased tissue. This suggests OSMR as an ideal target for therapy and this radioimmune therapy provides a novel treatment option for a disease with few therapy choices.

Patterns of care and outcomes of 417 patients with METAstatic SYNovial sarcoma (METASYN): real-life data from the French Sarcoma Group (FSG)

Background

Synovial sarcoma (SS) occurs in both adult and pediatric patients. The primary aim of this study is to describe the outcomes, prognostic factors, and treatment of patients with metastatic SS within a nationwide cohort.

Patients and methods

All pediatric and adult patients with metastatic SS are registered in the French Sarcoma Group database. Data were collected from the national database https://conticabase.sarcomabcb.org/ up to March 2020. Descriptive and comparative analyses were conducted using SAS 9.4 and Stata Special Edition 16.1 software.

Results

Between January 1981 and December 2019, 417 patients with metastatic SS from 17 French sarcoma centers were included, including 64 (15.3%) under the age of 26 years. Median age was 42.5 years (range 9-87 years). The metastases were synchronous (cohort 1) or metachronous (cohort 2) in 18.9% (N = 79) and 81.1% (N = 338) patients, respectively. Median overall survival (OS) from the date of metastasis was 22.3 months (95% confidence interval 19.7-24.1 months). First-line chemotherapy without ifosfamide and/or doxorubicin was unfavorable for progression-free survival and OS (P < 0.001). Concerning cohort 1, young age, surgery of the primary tumor, and single metastatic site were independent favorable prognostic factors for OS. In cohort 2, surgery within an expert French Sarcoma Group center, absence of chemotherapy in the perioperative setting, the lungs as a single metastatic site, time to first metastasis >12 months, local therapy, and ifosfamide in the first metastatic line were independent favorable prognostic factors.

Conclusions

The outcome of patients with metastatic SS is influenced by local treatment, management in reference centers, and cytotoxic treatments given in the perioperative and metastatic setting.

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METASYN is the largest retrospective study on metastatic adult and pediatric SS.

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This study confirms that surgery remains the mainstay for improving OS in reference centers.

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METASYN emphasizes the importance of focal treatment of metastases for OS.

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This study offers real-life results in a metastatic setting and is a useful support for developing new strategies.

Monophasic Synovial Sarcoma in the Elbow Misclassified but Successfully Treated as Ewing's Sarcoma with Chemotherapy

To the best of the authors’ knowledge, this is the first published case of monophasic synovial sarcoma (SS) initially diagnosed as Ewing’s sarcoma (ES), yet successfully treated with chemotherapy in a 24-year-old patient. The initial diagnosis showed a monotonous round cell tumor and positivity for CD99, characteristic of ES; however, the cytology was negative for the classic EWSR1 rearrangement of ES. The patient was treated with the standard chemotherapy protocol of ES – COG AEWS1031 Regimen A with vincristine, doxorubicin, cyclophosphamide, and mesna – as well as with wide resection. Post-resection tissue submission showed additional morphologic features which led to a re-evaluation of the classification of the tumor as well as additional molecular studies; these revealed positivity for translocations of SS18 (18q11.1) in 100% of the nuclei, which is most characteristic of SS, thus, reclassifying the neoplasm as a SS tumor. This case underscores the importance of considering several pathologic entities in the differential diagnosis of small, round blue cell tumors, including ES, SS, and lymphoma. It also demonstrates the importance of using chromosomal identification for a more definitive diagnosis, rather than relying on histological features and markers which are found in more than one tumor classification. There is conflicting evidence of the impact of chemotherapy on survival in SS, as it is primarily treated with radiation therapy. Since SS is rare, prospective studies on the effect of chemotherapy on survival are limited in number. However, our case study demonstrates that chemotherapy is another modality that can be used in the treatment of SS neoplasms.

The role of Ifosfamide-doxorubicin chemotherapy in histology-specific, high grade, locally advanced soft tissue sarcoma, a 14-year experience

PURPOSE

To compare long-term outcomes of high-grade, primary soft-tissue-sarcoma (STS), using Ifosfamide-Doxorubicin vs local therapy alone, in histology-specific sarcomas.

METHODS

Retrospective analysis was performed on 127 patients from 2005 to 2018, with high-grade STS of extremity or trunk, >5 cm, that were either Synovial-Cell, Dedifferentiated-Liposarcoma (DDL), Myxofibrosarcoma, Round-Cell-Liposarcoma (RCLS), Undifferentiated-Pleomorphic-Sarcoma (UPS), or Undifferentiated-Sarcoma-not-otherwise-specified (US-NOS), with central pathology review. Ifosfamide-Doxorubicin was generally given neoadjuvant over 5 cycles, followed by radiation and wide excision, with chemotherapy given in 38 patients, while 89 received local therapy alone. Multi-variable-analysis (MVA) of prognostic factors was performed, and local-recurrence-free-survival (LRFS), distant-metastases-free-survival (DMFS), disease-specific-survival (DSS), and overall-survival (OS) were estimated using Kaplan-Meier, and adjusted using propensity-score matching.

RESULTS

Median follow-up was 4.5 years. Younger age (p < 0.0001) and Synovial histology (p = 0.0002) were more likely to undergo chemotherapy. Ifosfamide-Doxorubicin improved 5-year DMFS (p = 0.02), DSS (p = 0.01), and OS (p = 0.01), by univariate comparisons, as well as sub-analysis of non-synovial histology, but significance was lost after propensity-score matching for DMFS (p = 0.10), DSS (p = 0.09), and OS (p = 0.07). Size >10 cm, trunk location, and lack of chemotherapy significantly lowered DMFS, DSS, and OS on MVA, while DDL had more favorable survival; although size, trunk location, and DDL histology were not significantly different between treatment groups. Ifosfamide-Doxorubicin independently improved DMFS (p = 0.001), DSS (p = 0.01), and OS (p = 0.001) on MVA.

CONCLUSION

Ifosfamide-Doxorubicin may be more beneficial in younger patients with >5 cm, high-grade, STS of the trunk or extremity in Synovial-Cell, DDL, Myxofibrosarcoma, RCLS, UPS, and US-NOS.

The Biology of Synovial Sarcoma: State-of-the-Art and Future Perspectives

New molecular insights are being achieved in synovial sarcoma (SS) that can provide new potential diagnostic and prognostic markers as well as therapeutic targets. In particular, the advancement of research on epigenomics and gene regulation is promising. The concrete hypothesis that the pathogenesis of SS might mainly depend on the disruption of the balance of the complex interaction between epigenomic regulatory complexes and the consequences on gene expression opens interesting new perspectives. The standard of care for primary SS is wide surgical resection combined with radiation in selected cases. The role of chemotherapy is still under refinement and can be considered in patients at high risk of metastasis or in those with advanced disease. Cytotoxic chemotherapy (anthracyclines, ifosfamide, trabectedin, and pazopanib) is the treatment of choice, despite several possible side effects. Many possible drug-able targets have been identified. However, the impact of these strategies in improving SS outcome is still limited, thus making current and future research strongly needed to improve the survival of patients with SS.

When SUV Matters: FDG PET/CT at Baseline Correlates with Survival in Soft Tissue and Ewing Sarcoma

Introduction: The role of positron-emission tomography/computed-tomography (PET/CT) in the management of sarcomas and as a prognostic tool has been studied. However, it remains unclear which metric is the most useful. We aimed to investigate if volume-based PET metrics (Tumor volume (TV) and total lesions glycolysis (TLG)) are superior to maximal standardized uptake value (SUVmax) and other metrics in predicting survival of patients with soft tissue and bone sarcomas. Materials and Methods: In this retrospective cohort study, we screened over 52′000 PET/CT scans to identify patients diagnosed with either soft tissue, bone or Ewing sarcoma and had a staging scan at our institution before initial therapy. We used a Wilcoxon signed-rank to assess which PET/CT metric was associated with survival in different patient subgroups. Receiver-Operating-Characteristic curve analysis was used to calculate cutoff values. Results: We identified a total of 88 patients with soft tissue (51), bone (26) or Ewing (11) sarcoma. Median age at presentation was 40 years (Range: 9–86 years). High SUVmax was most significantly associated with short survival (defined as <24 months) in soft tissue sarcoma (with a median and range of SUVmax 12.5 (8.8–16.0) in short (n = 18) and 5.5 (3.3–7.2) in long survival (≥24 months) (n = 31), with (p = 0.001). Similar results were seen in Ewing sarcoma (with a median and range of SUVmax 12.1 (7.6–14.7) in short (n = 6) and 3.7 (3.5–5.5) in long survival (n = 5), with (p = 0.017). However, no PET-specific metric but tumor-volume was significantly associated (p = 0.035) with survival in primary bone sarcomas (with a median and range of 217 cm³ (186–349) in short survival (n = 4) and 60 cm³ (22–104) in long survival (n = 19), with (p = 0.035). TLG was significantly inversely associated with long survival only in Ewing sarcoma (p = 0.03). Discussion: Our analysis shows that the outcome of soft tissue, bone and Ewing sarcomas is associated with different PET/CT metrics. We could not confirm the previously suggested superiority of volume-based metrics in soft tissue sarcomas, for which we found SUVmax to remain the best prognostic factor. However, bone sarcomas should probably be evaluated with tumor volume rather than FDG PET activity.

Preoperative versus Post-operative Radiotherapy for Extremity Soft tissue Sarcoma: a Systematic Review and Meta-analysis of Long-term Survival

BACKGROUND

The role of perioperative radiotherapy in the management of resectable extremity soft tissue sarcoma (ESTS) is widely recognised for local tumour control, wound complications (WC) and long-term function. However, debate continues regarding its implications on long-term survival. This study aimed to determine whether the timing of perioperative radiotherapy affects long-term survival outcomes in adults with ESTS.

METHODS

A systematic literature search of MEDLINE, EMBASE, Web of Science and Cochrane was performed. The primary outcome measure was the pooled hazard ratio (HR) at 95% confidence intervals. Secondary outcomes and subgroup analyses were presented as cumulative odds ratios (OR). A random-effects, generic inverse variance method and sensitivity analysis were performed to minimise heterogeneity.

RESULTS

Six studies (n = 4192 patients) were identified. Time-to-event analysis demonstrated a statistically significant advantage in post-operative radiotherapy for overall survival (HR 1.15 and p = 0.05). Combined HRs for disease-free (1.25 and p = 0.22) and disease-specific (1.06 and p = 0.43) survival also favoured post-operative radiotherapy but did not achieve statistical significance. Post-operative radiotherapy was shown to confer an overall (OR 1.19 and p = 0.01), disease-free (OR 1.19 and p = 0.01) and disease-specific (OR 1.19 and p = 0.01) survival advantage on subgroup analysis. This survival benefit was best observed at three years in the disease-free survival comparison (OR 1.55 and p = 0.003). Preoperative radiotherapy was associated with more WC (OR 2.74 and p<0.00001).

CONCLUSIONS

Pooled analysis of published literature suggests that post-operative radiotherapy confers a significant long-term survival advantage with fewer WC. Further large multicentre randomised controlled trials with long-term follow-up are required to determine the optimal perioperative radiotherapy regime in adult ESTS.

Synovial Sarcoma: A Clinical Review

Synovial sarcomas (SS) represent a unique subset of soft tissue sarcomas (STS) and account for 5–10% of all STS. Synovial sarcoma differs from other STS by the relatively young age at diagnosis and clinical presentation. Synovial sarcomas have unique genomic characteristics and are driven by a pathognomonic t(X;18) chromosomal translocation and subsequent formation of the SS18:SSX fusion oncogenes. Similar to other STS, diagnosis can be obtained from a combination of history, physical examination, magnetic resonance imaging, biopsy and subsequent pathology, immunohistochemistry and molecular analysis. Increasing size, age and tumor grade have been demonstrated to be negative predictive factors for both local disease recurrence and metastasis. Wide surgical excision remains the standard of care for definitive treatment with adjuvant radiation utilized for larger and deeper lesions. There remains controversy surrounding the role of chemotherapy in the treatment of SS and there appears to be survival benefit in certain populations. As the understanding of the molecular and immunologic characteristics of SS evolve, several potential systematic therapies have been proposed.

The management of pancreatic metastasis from synovial sarcoma of the soft tissue: A case report

Pancreatic metastases are rare, accounting for 2%–3% of pancreatic tumors. The pancreas represents an unusual metastatic site of synovial sarcoma (SS) outside the usual localizations (regional nodes, lung, bone, and liver). The diagnosis is evoked by the personnel medical history of SS and imaging then confirmed by histological examination of the guided pancreatic biopsy. Its therapeutic management is mainly surgical with extensive removal of the lesion. So far only four cases have been reported in the English literature. We reported the case of a male aged 30-year-old who was admitted to our Institute for a local recurrence of SS of the left thigh which was initially treated by surgical excision. The patient underwent a wide surgical excision followed by chemotherapy and radiotherapy. About 15 months later, he experienced a pancreatic metastasis of his SS. He had a caudal splenopancreatectomy with partial resection of the transverse colon followed by chemotherapy. This report highlights the diagnostic difficulties of this rare localization and therapeutic challenge.

Evaluation of conditional treatment effects of adjuvant treatments on patients with synovial sarcoma using Bayesian subgroup analysis

BACKGROUND

The impact of adjuvant chemotherapy or radiation therapy on the survival of patients with synovial sarcoma (SS), which is a rare soft-tissue sarcoma, remains controversial. Bayesian statistical approaches and propensity score matching can be employed to infer treatment effects using observational data. Thus, this study aimed to identify the individual treatment effects of adjuvant therapies on the overall survival of SS patients and recognize subgroups of patients who can benefit from specific treatments using Bayesian subgroup analyses.

METHODS

We analyzed data from patients with SS obtained from the surveillance, epidemiology, and end results (SEER) public database. These data were collected between 1984 and 2014. The treatment effects of chemotherapy and radiation therapy on overall survival were evaluated using propensity score matching. Subgroups that could benefit from radiation therapy or chemotherapy were identified using Bayesian subgroup analyses.

RESULTS

Based on a stratified Kaplan-Meier curve, chemotherapy exhibited a positive average causal effect on survival in patients with SS, whereas radiation therapy did not. The optimal subgroup for chemotherapy includes the following covariates: older than 20 years, male, large tumor (longest diameter > 5 cm), advanced stage (SEER 3), extremity location, and spindle cell type. The optimal subgroup for radiation therapy includes the following covariates: older than 20 years, male, large tumor (longest diameter > 5 cm), early stage (SEER 1), extremity location, and biphasic type.

CONCLUSION

In this study, we identified high-risk patients whose variables include age (age > 20 years), gender, tumor size, tumor location, and poor prognosis without adjuvant treatment. Radiation therapy should be considered in the early stages for high-risk patients with biphasic types. Conversely, chemotherapy should be considered for late-stage high-risk SS patients with spindle cell types.

Skp2 depletion reduces tumor-initiating properties and promotes apoptosis in synovial sarcoma

Synovial sarcoma (SS) is an aggressive soft-tissue cancer with a poor prognosis and a propensity for local recurrence and distant metastasis. In this study, we investigated whether S phase kinase-associated protein (Skp2) plays an oncogenic role in tumor initiation, progression, and metastasis of SS. Our study revealed that Skp2 is frequently overexpressed in SS specimens and SS18-SSX transgenic mouse tumors, as well as correlated with clinical stages. Next, we identified that genetic depletion of Skp2 reduced mesenchymal and stemness markers, and inhibited the invasive and proliferative capacities of SS cell lines. Furthermore, Skp2 depletion markedly suppressed the growth of SS xenografts tumors. Treatment of SS cell lines with the skp2 inhibitor flavokawain A (FKA) reduced Skp2 expression in a dose-dependent manner and resulted in cell cycle arrest and apoptosis. FKA also suppressed the invasion and tumor-initiating properties in SS, similar to the effects of Skp2 knockdown. In addition, a combination of FKA and conventional chemotherapy showed a synergistic therapeutic efficacy. Taken together, our results suggest that Skp2 plays an essential role in the biology of SS by promoting the mesenchymal state and cancer stemness. Given that chemotherapy resistance is often associated with cancer stemness, strategies of combining Skp2 inhibitors with conventional chemotherapy in SS may be desirable.

The Long-Term Outcomes of Intensive Combined Therapy of Adult Patients with Localised Synovial Sarcoma

Introduction: Synovial sarcoma (SaSy) is a high-grade, malignant soft tissue sarcoma (STS) accounting for 5–9% of STS. The aim of this study was to analyse outcomes of patients with localised SaSy treated in a single institution with a uniform neo- and adjuvant-combined therapy protocol. Methods: 171 patients with stage II/III SaSy were treated between 1997 and 2014. Chemotherapy consisted of 4 cycles of ifosfamide 12 g/m² and two cycles of a doxorubicin-based regimen 75 mg/m². With the exception of patients who underwent amputation, all patients received neoadjuvant radiotherapy. Results: Median age was 33 years (range 17–69). Tumours larger than 5 cm in size were found in 70% of patients. The 5-year overall survival (OS), local relapse-free survival (LRFS) and metastasis-free survival (MFS) rates were 75%, 80% and 60%, respectively. In multivariate Cox’s regression, age > 35 years, male sex, larger tumour size and histology other than monophasic were associated with worse OS. Conclusions: In adult patients with localised SaSy, long-term survival can be achieved in a significant proportion of cases with intensive combined therapy. The multivariate analysis identified age, sex, disease stage and histology subtype as independent prognostic factors of OS.

The survival and prognosis analysis of synovial sarcoma subtypes: a Surveillance, Epidemiology, and End Results population-based analysis

PURPOSE

By comparing epidemiologic and prognostic data of synovial sarcoma subtypes, this study aims to clarify the difference in prognosis and risk factors among different synovial sarcoma subtypes.

METHODS

In total, 1692 patients with synovial sarcoma in the USA who were diagnosed during 1975 through 2016 and retrieved from the Surveillance, Epidemiology, and End Results (SEER) program were studied.

RESULTS

There were statistically significant differences in the distribution of age and race among three synovial sarcoma subtypes, while no major differences in the distribution of sex, tumor stage, and tumour size were found. The highest five and ten year survival rates were found in the biphasic subtype (69%, 60%), followed by the monophasic subtype (59%, 49%), and lowest in the epithelioid subtype (32%, 26%). Age and SEER historic stage were the two demographic factors that found to have statistically significant impact on survival in all subtypes. Radiation was found to be protective in the monophasic subtype (HR 0.61, p < 0.001).

CONCLUSION

Among different synovial sarcoma subtypes, the biphasic subtype favoured the best survival, while the epithelioid cell subtype was associated with the worst. Male and black race were independently associated with worse survival only in the monophasic subtype. Radiotherapy could provide significant benefit for patients with the monophasic synovial sarcoma.

Systematic literature review of clinical outcomes in adults with metastatic or advanced synovial sarcoma

Background: Synovial sarcoma (SS) is a rare, aggressive soft tissue sarcoma with a poor prognosis after metastasis. The objective of this study was to conduct a systematic review of the clinical evidence for therapeutic options for adults with metastatic or advanced SS. Materials & methods: Relevant databases were searched with predefined keywords. Results: Thirty-nine publications reported clinical data for systemic treatment and other interventions. Data on survival outcomes varied but were generally poor (progression-free survival: 1.0-7.7 months; overall survival: 6.7-29.2 months) for adults with metastatic and advanced SS. A high frequency of neutropenia with systemic treatment and low quality of life post-progression were reported. Conclusion: Reported evidence suggests poor outcomes in adults with metastatic and advanced SS and the need for the development of new treatment modalities.

HLA Genotyping in Synovial Sarcoma: Identifying HLA-A*02 and Its Association with Clinical Outcome

PURPOSE

To determine if a targeted exome panel utilizing matched normal DNA can accurately detect germline and somatic HLA genes in patients with synovial sarcoma (SS) and whether select HLA-A*02 genotypes are prognostic or predictive of outcome in metastatic SS.

EXPERIMENTAL DESIGN

Patients with metastatic SS consented to HLA typing by a Clinical Laboratory Improvement Amendments (CLIA)-certified test to determine eligibility for a clinical trial of NY-ESO-1-specific engineered T cells restricted to carriers of HLA-A*02:01, -A*02:05, or -A*02:06 (HLA-A*02 eligible). HLA genotype was determined from Memorial Sloan Kettering Integrated Molecular Profiling of Actionable Cancer Targets (MSK-IMPACT), where feasible, and somatic loss of heterozygosity (LOH) in HLA alleles was identified. Overall survival (OS) was estimated and stratified by HLA-A*02 eligibility.

RESULTS

A total of 23 patients had HLA genotyping by a CLIA-certified lab and MSK-IMPACT. Ninety percent (108/110) of the sequenced alleles were concordant between IMPACT and the outside lab. LOH of HLA genes was detected in three tumors, one had loss of HLA-A*02:01. In total, 66 patients were screened for T-cell therapy and 20 (30%) were HLA-A*02 eligible on outside testing. Univariate analysis of OS from the time of metastasis found HLA-A*02 eligibility was marginally associated with shorter OS [HR = 1.95; 95% confidence interval (CI), 0.995-3.813; P = 0.052]. On multivariate analysis, older age and larger tumor size, but not HLA-A*02 eligibility, were significantly associated with decreased OS. HLA-A*02 eligibility did not impact OS after chemotherapy or pazopanib in the metastatic setting.

CONCLUSIONS

Targeted gene panels like MSK-IMPACT may accurately report HLA type and identify loss of somatic HLA alleles. In a multivariable model, HLA-A*02 eligibility was not significantly associated with OS in patients with metastatic SS.

Radiotherapy is Associated With Improved Survival in Patients With Synovial Sarcoma Undergoing Surgery: A National Cancer Database Analysis

BACKGROUND

Previous studies have demonstrated an association of perioperative radiotherapy (RT) with improved survival in patients with synovial sarcoma (SS) undergoing surgery, but the mechanism for this is unknown. In this study, we sought to further analyze this association using a hospital-based data set where data on chemotherapy administration and surgical margin status are available.

METHODS

Using the National Cancer Database, we identified 1216 patients with SS (aged ≥18 y) from 2004-2012 undergoing surgery. Cox proportional hazards analysis was used to study the effect of clinicopathologic variables on overall survival (OS).

RESULTS

Mean age at diagnosis was 41.5 y (range 18-90), and 71.3% of tumors were high grade; 22.9% underwent surgery alone, 59.6% received RT with surgery, 44.2% received chemotherapy with surgery, and 26.3% received trimodality therapy. Age, sex, grade, Charlson-Deyo score, and RT (hazard ratio, 0.676; 95% confidence interval, 0.519-0.880; P = 0.004) were associated with improved OS, whereas chemotherapy (hazard ratio, 1.20; 95% confidence interval, 0.899-1.60; P = 0.217) and surgical margin status were not. Trimodality therapy with surgery, RT, and chemotherapy was associated with improved OS when compared with therapy with surgery and chemotherapy alone.

CONCLUSIONS

In patients with SS undergoing surgery, we observed a significant improved association of OS with the addition of RT when adjusting for comorbidity score, margin status, and receipt of chemotherapy. These data further support routine implementation of RT in the treatment of patients with SS, including those receiving aggressive multimodality and trimodality care.

Treatment of limb synovial sarcoma with metastasis at presentation

Limb synovial sarcoma (LSS) patients with metastasis at presentation usually have a very poor prognosis. Little is known about survival prediction and risk factors in these patients owing to the condition's rarity. Thus, this study examined the survival and prognostic variables of metastatic LSS.Clinical data for LSS patients with metastasis at presentation from 1975 to 2016 were obtained from the surveillance, epidemiology, and end results database. The Kaplan-Meier method was used to determine the survival curves. Univariate and multivariate Cox regression analysis were conducted to identify the prognostic predictors.The study enrolled 217 patients. Male predominance was observed in the metastatic LSS group. The median age at diagnosis of this population was 40 years. The subtypes were "not otherwise specified" (49.8%), spindle cell (32.7%), biphasic (17.1%), and epithelioid cell (0.5%). The 3-year overall and cancer-specific survival rates of the entire group were 27.2% and 28.3%, respectively. Tumor size <10 cm, surgery, radiotherapy, and chemotherapy were independent predictors of improved overall and cancer-specific survival in the multivariate analyses.Comprehensive treatment for LSS patients with metastasis at diagnosis is necessary and effective and can prolong survival.

Soft Tissue Tumors of the Extremity

Although the vast majority of soft tissue extremity masses are benign, approximately 13,000 people in the United States were diagnosed with soft tissue sarcoma in 2019. This article focuses on the optimal workup of soft tissue masses including the indications for ultrasound and MRI, as well as use of preoperative core needle biopsy. Current AJCC staging, surgical principles of soft tissue sarcoma management, and data regarding indications for radiation therapy and chemotherapy are reviewed. As up to 50% of patients with soft tissue sarcoma will develop recurrent disease, surgical management of locally recurrent and distant metastatic disease is discussed.

Precision Medicine in Soft Tissue Sarcoma Treatment

Soft tissue sarcoma (STS) is a rare component of malignant diseases. STS includes various histological subtypes, and there are some important differences among the different histological subtypes regarding the mutation profile and sensitivity to antitumor agents. Many clinical trials of STS incorporating many different histological subtypes in various populations have been conducted; it is difficult to compare the findings and make conclusions about clinical efficacy. Targeted therapies focusing on specific histological subtypes and precision therapy focusing on the specific genetic mutation(s) of each STS patient are being investigated. Since STS patients are a small population, new clinical trial designs are required to evaluate and establish new targeted therapies for each histological subtype that has a limited number of patients, and preclinical investigations are needed to detect targetable mutations. Now that cancer genome profiling is used in clinical practice, it is urgently necessary to connect the genome profiling data obtained in clinical settings to the optimal clinical treatment strategies. Herein we review the development and challenges of precision therapy in the management of STS patients.

Clinical and strategic outcomes of metastatic synovial sarcoma on limb

OBJECTIVE

Synovial sarcoma (SS) is one of the most frequent malignant soft-tissue tumors, and nearly 65% arise in the lower extremities. Survival prediction and the risk factors of the patients are poorly understood. Thus, this study examined the survival and prognostic variables of metastatic limb SS (LSS).

METHODS

Clinical data of LSS patients with metastasis at the presentation from 1975 to 2017 were obtained from the Surveillance, Epidemiology, and End Results database program database. Kaplan-Meier method was used to describe the survival curves. Univariate and multivariate Cox regression analysis were conducted to reveal the real prognostic predictors.

RESULTS

Male predominance was observed in the metastatic LSS group from a total number of 217 patients. This population was composed of 49.8% not other specified subtype, 32.7% spindle cell subtype, 17.1% biphasic subtype, and 0.5% epithelioid cell subtype. The 3-year overall survival (OS) and cancer-specific survival (CSS) rates of the entire group were 27.2% and 28.3%, respectively. Tumor size <10 cm, surgery, radiotherapy, and chemotherapy were calculated as independent predictors of improved OS and CSS by multivariate analyses.

CONCLUSION

SS is still a disease with a poor prognosis. This can increase the survival rate and time by the well-planned treatment.

Synovial sarcoma mimicking a traumatic pseudoaneurysm in the upper extremity

Synovial sarcomas are a rare but aggressive malignancy that primarily affects young patients. Diagnosis is often difficult and delayed due to its insidious onset, heterogenous presentation and mimicry of other pathologies. We present the case of a patient with a history of a slow-growing left arm mass that arose after a traumatic fracture of the humerus. Multimodal imaging was undertaken and reported the mass as being consistent with a vascular malformation of the brachial artery. The patient underwent surgical repair of the artery and intraoperative biopsies confirmed a diagnosis of synovial sarcoma. This case highlights the importance of maintaining suspicion for soft-tissue sarcomas in young patients presenting with a mass, and demonstrates the way in which these tumours may mimic other pathologies both clinically and radiologically. Early referral to a specialist sarcoma centre is key for further investigative workup.

Trends in the Use of Adjuvant Chemotherapy for High-Grade Truncal and Extremity Soft Tissue Sarcomas

BACKGROUND

In the randomized controlled trial (RCT) EORTC 62931, adjuvant chemotherapy failed to show improvement in relapse-free survival (RFS) or overall survival (OS) for patients with resected high-grade soft tissue sarcoma (STS). We evaluated whether the negative results of this 2012 RCT have influenced multidisciplinary treatment patterns for patients with high-grade STS undergoing resection at seven academic referral centers.

METHODS

The U.S. Sarcoma Collaborative database was queried to identify patients who underwent curative-intent resection of primary high-grade truncal or extremity STS from 2000 to 2016. Patients with recurrent tumors, metastatic disease, and those receiving neoadjuvant chemotherapy were excluded. Patients were divided by treatment era into early (2000-2011, pre-European Organisation for Research and Treatment of Cancer [EORTC] trial) and late (2012-2016, post-EORTC trial) cohorts for analysis. Rates of adjuvant chemotherapy and clinicopathologic variables were compared between the two cohorts. Univariate and multivariate regression analyses were used to determine factors associated with OS and RFS.

RESULTS

949 patients who met inclusion criteria were identified, with 730 patients in the early cohort and 219 in the late cohort. Adjuvant chemotherapy rates were similar between the early and late cohorts (15.6% versus 14.6%; P = 0.73). Patients within the early and late cohorts demonstrated similar median OS (128 months versus median not reached, P = 0.84) and RFS (107 months versus median not reached, P = 0.94). Receipt of adjuvant chemotherapy was associated with larger tumor size (13.6 versus 8.9 cm, P < 0.001), younger age (53.3 versus 63.7 years, P < 0.001), and receipt of adjuvant radiation (P < 0.001). On multivariate regression analysis, risk factors associated with decreased OS were increasing American Society of Anesthesiologists class (P = 0.02), increasing tumor size (P < 0.001), and margin-positive resection (P = 0.01). Adjuvant chemotherapy was not associated with OS (P = 0.88). Risk factors associated with decreased RFS included increasing tumor size (P < 0.001) and margin-positive resection (P = 0.03); adjuvant chemotherapy was not associated with RFS (P = 0.23).

CONCLUSIONS

Rates of adjuvant chemotherapy for resected high-grade truncal or extremity STS have not decreased over time within the U.S. Sarcoma Collaborative, despite RCT data suggesting a lack of efficacy. In this retrospective multi-institutional analysis, adjuvant chemotherapy was not associated with RFS or OS on multivariate analysis, consistent with the results from EORTC 62931. Rates of adjuvant chemotherapy for high-grade STS were low in both cohorts but may be influenced more by selection bias based on clinicopathologic variables such as tumor size, margin status, and patient age than by prospective, randomized data.

Synovial sarcoma in the plantar region: A case report and literature review

BACKGROUND

Synovial sarcoma (SS), a rare malignant soft tissue tumor whose histological origin is still unknown, often occurs in limbs in young people and is easily misdiagnosed.

CASE SUMMARY

We report a 24-year-old man who sought treatment for plantar pain thought to be caused by a foot injury that occurred 4 years prior. Currently, he had been seen at another hospital for a 1-wk history of unexplained pain in the left plantar region and was treated with acupuncture, a kind of therapy of Chinese medicine, which partly relieved the pain. Because of this, the final diagnosis of biphasic SS was made after two subsequent treatments by pathological evaluation after the last operation. SS is rarely seen in the plantar area, and his history of a left plantar injury confused the original diagnosis.

CONCLUSION

This study shows that pathological and imaging examinations may play a vital role in the early diagnosis and treatment of SS.

A Retrospective Case Series of Synovial Sarcoma of the Upper Extremity

Purpose

Previous studies have grouped the treatment of axial and appendicular synovial sarcomas. The purpose of this study was to assess the prognostic variables of upper extremity synovial sarcomas (UESS) and compare the outcomes of those who underwent a nononcologic or inadvertent excision prior to definitive resection to those who underwent an initial oncologic resection.

Methods

We reviewed the records of 23 UESS treated with definitive surgery at our institution between 1990 and 2014. There were 13 women and 10 men with a median age of 30 years (6–60) and median follow-up of 63 months (15–248). Prognostic variables, recurrence-free survival (RFS), and overall survival (OS) were then assessed.

Results

Fifteen patients (65%) had a prior unplanned excision. Five patients required an amputation to obtain local control of disease. There were 3 observed local recurrences and 2 distant metastases at a median of 45 months from presentation. We found no difference in need for amputation, RFS, or OS between those who had undergone a planned excision and those who had an unplanned excision.

Conclusion

While we were unable to find a significant difference in outcomes or amputation rates between those who underwent reexcision of a previously unplanned excision and those who underwent an initial planned resection, the high rate of unplanned excision is troubling and should remind practitioners to consider sarcoma in the differential of all upper extremity masses.

Metastatic Synovial Sarcoma: Experience from a Tertiary Care Center from India

Background: Synovial sarcoma represents 8% of all soft-tissue sarcoma (STS). It is a high-grade STS, and 50% of patients develop metastasis. The most common site of metastasis is the lungs, lymph nodes followed by bones. Ifosfamide-based chemotherapy is associated with improved outcome. In this study, we report our experience of metastatic synovial sarcoma according to primary sites, metastatic pattern, and their outcome. Materials and Methods: This was a retrospective observational study carried out at our institute from January 2013 to December 2016. The aim of our study was to evaluate the pattern of metastasis, response to chemotherapy, and survival in patients with metastatic synovial sarcoma. Results: Over a period of 4 years, 43 patients with metastatic synovial sarcoma were diagnosed with median age of 30 years. Nearly 70% of patients had lung metastasis, other site of metastasis were lymph node, bone, and liver. Thirty patients received chemotherapy with a combination of ifosfamide and doxorubicin. The overall response rate was 87% with median progression-free survival of 8 months. Patients with lung only metastasis had better survival compared with nonpulmonary metastatic site (18 months vs. 12 months). The median survival was 18 months. Conclusion: Metastatic synovial sarcoma is chemoresponsive tumor with lung being the most common metastatic site. Patients with lung only metastasis had a better outcome than nonpulmonary metastasis.

Favorable outcomes of localized synovial sarcoma patients with a high utilization rate of neoadjuvant and/or adjuvant chemotherapy

Synovial sarcoma (SS) is considered to be a chemosensitive, soft tissue sarcoma. Therefore, neoadjuvant and/or adjuvant chemotherapy (N/AC) is used for the treatment of high-risk SS patients. However, the role of N/AC remains controversial. The present study aimed to review the clinical outcomes of surgically treated localized SS and investigate the effects of N/AC with long-term observation. The clinical outcomes of 54 patients with surgically treated localized SS were retrospectively analyzed. The median patient age was 42 years (range, 8-81 years), and the median follow-up period was 94 months for survivors (range, 7-220 months). A total of 38 patients (70%) received chemotherapy. Of these, 32 (59%) patients received neoadjuvant chemotherapy, 33 (61%) received adjuvant chemotherapy, and 27 (50%) received neoadjuvant and adjuvant chemotherapy. Fourteen patients (26%) received adjuvant radiotherapy. Three patients (6%) had local recurrence and 13 patients (24%) developed distant metastasis. The overall survival (OS) rates at 5 and 10 years were 87 and 84%, respectively. N/AC did not improve survival. In conclusion, we found satisfactory long-term OS among patients with a high utilization rate of N/AC. Further study should be necessary to evaluate which population of SS would benefit from N/AC.

Pazopanib regresses a doxorubicin-resistant synovial sarcoma in a patient-derived orthotopic xenograft mouse model

Synovial sarcoma (SS) is an aggressive subgroup of soft tissue sarcoma (STS) with high grade and high risk of metastasis. However, there are no systemic therapies available that target SS. Therefore, transformative therapy is needed for SS. To establish a patient-derived orthotopic xenograft (PDOX) model, a patient tumor with high grade SS from a lower extremity was grown orthotopically in the right biceps femoris muscle of mice. To test the efficacy of drugs, the PDOX models were randomized into five groups: Group 1 (G1), control-without treatment; Group 2 (G2), doxorubicin (DOX); Group 3 (G3), temozolomide (TEM); Group 4 (G4), gemcitabine (GEM) combined with docetaxel (DOC); and Group 5 (G5), pazopanib (PAZ). Tumor size and body weight were measured twice a week for each treatment group. A significant growth inhibition was found on day 14 in each treatment group compared to the untreated control, except for DOX. However, PAZ was significantly more effective than both TEM and GEM + DOC. In addition, PAZ significantly regressed the tumor volume on day 14 compared to day 0. No change was found in body weight on day 14 compared to day 0 in any treatment group. The present study demonstrated the precision of the SS PDOX models for individualizing SS therapy.

Standard treatment and emerging drugs for managing synovial sarcoma: adult's and pediatric oncologist perspective

INTRODUCTION

in this review we discuss the standard of care for both pediatric and adult synovial sarcoma (SS), the prognostic differences between them, and the treatments available for localized and advanced diseases. We also overview the biology and the recent drugs under consideration in clinical trials on SS. Areas covered: we focus on new targeted therapies being investigated for advanced SS, especially anti-angiogenic drugs, and immunotherapy. We review all the published data and ongoing trials dedicated to SS or to soft tissue sarcoma in general, paying particular attention to the results obtained in SS patients. Expert opinion: we expect new treatment strategies to become available for SS in the near future. The ongoing and published trials on targeted therapies and immunotherapy mainly concern adult patients, but the somatic biology of pediatric SS has some similarities as in adult disease. A stronger cooperation between adult and pediatric oncologists in recent years has led to a more shared effort to find new treatment strategies for advanced SS patients, regardless of their age.

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.

Epigenetic Changes at the Birc5 Promoter Induced by YM155 in Synovial Sarcoma

YM155 is an anti-cancer therapy that has advanced into 11 different human clinical trials to treat various cancers. This apoptosis-inducing therapy indirectly affects the protein levels of survivin (gene: Birc5), but the molecular underpinnings of the mechanism remain largely unknown. Synovial sarcoma is a rare soft-tissue malignancy with high protein expression of survivin. We investigated whether YM155 would be a viable therapeutic option to treat synovial sarcoma. YM155 therapy was applied to human synovial sarcoma cell lines and to a genetically engineered mouse model of synovial sarcoma. We discovered that YM155 exhibited nanomolar potency against human synovial sarcoma cell lines and the treated mice with synovial sarcoma demonstrated a 50% reduction in tumor volume compared to control treated mice. We further investigated the mechanism of action of YM155 by looking at the change of lysine modifications of the histone tails that were within 250 base pairs of the Birc5 promoter. Using chromatin immunoprecipitation (ChIP)-qPCR, we discovered that the histone epigenetic marks of H3K27 for the Birc5 promoter changed upon YM155 treatment. H3K27me3 and H3K27ac increased, but the net result was decreased Birc5/survivin expression. Furthermore, the combination of molecular events resulted in caspase 3/7/8 upregulation and death of the sarcoma cells.

Genetic and molecular reappraisal of spindle cell adamantinoma of bone reveals a small subset of misclassified intraosseous synovial sarcoma

Adamantinoma represents a distinct group of bone tumors showing both mesenchymal and epithelial differentiation most commonly involving the tibial diaphysis. Most adamantinomas contain a fibro-osseous component and an epithelial component consisting of squamous or basaloid cells. Adamantinomas are considered malignant neoplasms requiring en bloc excision that frequently recur locally and can rarely metastasize. Rare adamantinomas show an epithelial component consisting predominantly of monomorphic spindle cells, which, combined with an epithelial immunophenotype, can mimic monophasic synovial sarcoma. Synovial sarcoma is very rare in bone. It is considered a high-grade sarcoma that typically necessitates chemotherapy. However, the relationship between spindle cell adamantinoma and intraosseous synovial sarcoma has not been investigated. The current study was prompted by identification of a presumed spindle cell adamantinoma of the tibia with diffuse keratin expression that harbored a SS18 gene region rearrangement. FISH of eight additional bone tumors initially classified as spindle cell adamantinoma based on clinicoradiopathologic findings revealed one additional case with SS18 rearrangement. Histologically, both intraosseous synovial sarcoma and spindle cell adamantinoma demonstrated uniform fusiform nuclei with scant cytoplasm, short fascicles and low mitotic activity. The adamantinomas, but not the synovial sarcomas, were more likely to show overt epithelial differentiation in the form of pseudoglands or squamous nests. Immunohistochemistry of all cases, irrespective of SS18 status, showed diffuse keratin positivity in the spindle cell component, and less consistent EMA positivity. Clinical follow-up was available in both intraosseous synovial sarcomas, one of which recurred and the other metastasized. Two of the six spindle cell adamantinomas with follow-up metastasized. The above findings highlight the morphologic and immunophenotypic overlap between spindle cell adamantinoma and intraosseous synovial sarcoma of the tibia. Investigation of SS18 status to exclude synovial sarcoma is suggested prior to rendering a diagnosis of spindle cell adamantinoma.

Concurrent Papillary Thyroid Carcinoma and Synovial Carcinoma of the Neck in an Adult Male

INTRODUCTION

Synovial sarcoma makes up 8-10% of all soft tissue sarcomas, and constitutes 3-10% of all sarcomas occurring in the head and neck region. It shows male predominance (3:2), and the mean age of presentation is 30 years.

CASE REPORT

A 51-year-old gentleman presented with right-sided neck swelling which had been progressively increasing in size for the past 2 years. A computed tomography (CT) scan revealed a large heterogeneously enhancing mass on the right side of the neck measuring 7.5 × 6.2 cm. Biopsy of an enlarged node revealed papillary thyroid carcinoma. The patient subsequently underwent total thyroidectomy with right neck dissection. Final histopathology revealed a papillary carcinoma of the thyroid, and the right-sided mass was shown to be monophasic synovial sarcoma.

CONCLUSION

We present a case of a concurrent pathology of neck papillary thyroid carcinoma with monophasic synovial sarcoma. We experienced difficulty in diagnosis and misdirection due to raised C-reactive protein (CRP) levels, until final histopathology of the neck mass.

The Future of Radiation Oncology in Soft Tissue Sarcoma

Radiotherapy (RT) is an important component of the treatment of soft tissue sarcomas (STS) and has been traditionally incorporated with a homogenous approach despite the reality that STS displays a known heterogeneity in clinicopathologic features and treatment outcomes. In this article, we explore the principle components of personalized medicine, including genomics, radiomics, and treatment response, along with their impact on the future of radiation therapy for STS. We propose a shift in the treatment paradigm for STS from a one-size-fits-all technique to one that implements the tenets of personalized medicine and includes the framework for a potential clinical trial technique in this heterogeneous disease.

Systemic Anti-Cancer Therapy in Synovial Sarcoma: A Systematic Review

Synovial sarcoma (SS) is an aggressive malignancy which accounts for approximately 5–10% of all soft-tissue sarcomas. SS has pathologic and genomic characteristics that define it as a distinct subtype of soft tissue sarcoma (STS). STS subtypes continue to be recognized as distinct entities with specific characteristics, including differential chemo-sensitivity. The objective of this study was to conduct a descriptive review of current data on survival outcomes of systemic anti-cancer therapy specific to SS. A systematic literature review was conducted, using a custom search strategy to search EMBASE, Medline and CENTRAL for clinical trials and observational studies reporting overall survival (OS), progression-free survival (PFS) and/or response for cohorts of at least 50 SS patients. We identified 28 studies meeting these criteria, 25 of which were retrospective studies. Only three prospective studies were identified. Survival reports varied widely between studies based on the population, in particular on the disease stage, and reporting was heterogeneous in terms of the time points reported on. For patients with localized disease, reports of five-year PFS ranged from 26% to 80.7% and five-year OS from 40% to 90.7%, whereas five-year OS for patients with metastatic disease was very low at around 10%; and in one case, 0% was reported. Only four of the included publications reported outcomes by type of systemic anti-cancer therapy received. Our study draws attention to the fact that additional prospective studies to better define the most appropriate treatment for SS in all stages and lines of therapy are still needed.

Surgical management and outcome of synovial sarcoma in the spine

Background

Synovial sarcoma (SS) is a soft tissue sarcoma that rarely occurs in the spine, and a minimal number of cases have been reported in the literature. Spinal SS is challenging in diagnosis and treatment and has a poor prognosis. The aim of this study was to summarize and analyse the clinical features and outcomes of patients with spinal SS.

Methods

A total of 16 cases of patients with spinal SS admitted to our institution were reviewed retrospectively. General information, radiological findings and treatment strategies were collected. These patients were followed up regarding their continuing treatment, local or distant recurrence and survival.

Results

Spinal SS patients in this series ranged in age from 12 to 68 years (median, 33). Four en bloc resections and 12 piecemeal resections were performed. Improved Frankel (P = 0.002), visual analogue scale (P = 0.002) and Karnofsky Performance Status (P = 0.002) scores were seen postoperatively. The mean follow-up period was 35.9 ± 23.5 (median 31.5, range 4–87) months, with four local recurrences and three distant metastases detected. Eight patients (50.0%) died of disease by the last follow-up. The 1-, 3- and 5-year overall survival rates were 87.5%, 61.4% and 40.9%, respectively. Preoperative chemotherapy was used in three patients to facilitate surgical resection, and adjuvant chemotherapy and radiotherapy were used in six patients.

Conclusions

Spinal SS has a relatively high risk of local recurrence and distant metastasis. Surgical intervention can improve the neurological function and relieve pain in these patients. En bloc excision is an effective treatment strategy to improve survival and prevent local recurrence. Management of spinal SS should be under the instruction of a multidisciplinary team.

The challenge of the management of adolescents and young adults with soft tissue sarcomas

Soft tissue sarcomas are relatively frequent in adolescents and young adults and their clinical management may be complex, partly due to tumor associated factors, but also because different approaches have been adopted by pediatric and adult medical oncologists dealing with the same disease. However, times are changing and in the last few years, management has tended to converge towards a common strategy. Continued and increased international collaboration between pediatric and adult sarcoma groups is of critical importance to improve the quality of treatment as well as research programs dedicated to young patients with soft tissue sarcomas.