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.

Therapeutic approaches for spinal synovial sarcoma: a comprehensive review of the literature.

OBJECTIVE: Synovial sarcoma (SS) is a relatively rare type of soft-tissue sarcoma that is commonly treated with surgery, radiation, chemotherapy, and palliative care. Stereotactic radiosurgery (SRS) is an emerging approach that shows promise in treating CNS conditions, but it has not been studied for SS. The authors present a systematic review that explores the effectiveness of different treatments, with a focus on SRS, for managing spinal SS. METHODS: A systematic PubMed search was conducted that covered studies from 1964 to 2022, yielding 70 relevant studies. Inclusion criteria encompassed primary and metastatic spinal SS, various treatment modalities, patient age 17 years or older, English-language studies, retrospective series, and case reports. Based on these criteria, 26 studies were included in this review and 44 were excluded. RESULTS: Of the included studies, 15 patients from 9 studies were treated with surgical intervention followed by both conventional radiotherapy (RT) and chemotherapy, 10 patients from 10 studies were treated with surgery followed by RT, 5 studies comprising 8 patients were exclusively treated with surgery, 5 cases in 3 studies were treated with surgery plus concomitant chemotherapy, 4 patients in 2 studies were treated with SRS, and only 1 study reported treatment without surgery and with chemotherapy and RT. The median progression-free survival and overall survival periods observed in the SRS-treated patients were 37 months and 60 months, respectively, which were higher than those of any other treatment method or combination used. CONCLUSIONS: The authors' study offers a thorough review of spinal SS treatments. They are hopeful that this will aid clinicians in informed decision-making for better patient outcomes.

Synovial Sarcoma of the Gastrointestinal Tract.

We report the clinicopathologic and immunohistochemical features of 18 cases of confirmed primary synovial sarcoma of the gastrointestinal tract. The neoplasms arose in 10 women and 8 men ranging in age from 23 to 81 years (mean: 50; median: 57.5 years). The tumors for which size was known ranged from 1.8 to 15.0 cm (mean: 5.2; median: 5.1 cm). Microscopically, 14 synovial sarcomas were of the monophasic type, 2 were biphasic, and 2 were poorly differentiated. Immunohistochemical analysis of 4 cases showed strong, diffuse staining for SS18::SSX (4/4 cases). Pancytokeratin and EMA immunohistochemistry were performed on 13 and 9 tumors, respectively, and each showed patchy-to-diffuse staining. By reverse-transcription PCR, 3 cases were positive for the SS18::SSX1, and 2 cases were positive for the SS18::SSX2 gene fusion. Six cases contained an SS18 gene rearrangement by fluorescence in situ hybridization, and next-generation sequencing identified an SS18::SSX2 gene fusion in one case. Clinical follow-up information was available for 9 patients (4 months to 4.6 years; mean, 2.8 y; median: 29 months), and one patient had a recent diagnosis. Three patients died of disease within 41 to 72 months (mean, 56 months) of their diagnosis. Five patients were alive without evidence of disease 4 to 52 months (mean, 17.6 months) after surgery; of whom 1 of the patients received additional chemotherapy treatment after surgery because of recurrence of the disease. A single patient was alive with intraabdominal recurrence 13 months after surgery. We conclude that synovial sarcoma of the gastrointestinal tract is an aggressive tumor, similar to its soft tissue counterpart, with adverse patient outcomes. It is important to distinguish it from morphologically similar gastrointestinal tract lesions that may have different treatment regimens and prognoses.

Team Approach: Extremity Soft Tissue Sarcoma.

¼ Synovial sarcoma is a soft tissue sarcoma that most commonly presents in the extremity in a periarticular location.¼ 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.¼ 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.

Primary synovial sarcoma and acinar adenocarcinoma of prostate rarely occur simultaneously: A case report.

RATIONALE: Primary synovial sarcoma of the prostate is an extremely rare mesenchymal malignant soft tissue tumor with unique morphological features. Synovial sarcoma often occurs in the pararticular tissues of limbs in young people, but rarely occurs in prostate. Because it is very rare, it is easily misdiagnosed as benign prostatic hyperplasia or prostate cancer clinically. A case of synchronous acinar adenocarcinoma of the prostate has not been reported. In this article, we report a unique case of primary prostatic synovial sarcoma with acinar adenocarcinoma. PATIENT CONCERNS: A 58-year-old male patient was found to have a prostate mass during physical examination. Prostate ultrasound examination showed an increase in prostate volume of 5.2 × 3.3 × 3.3 cm, mixed echo mass can be seen on the left side of the prostate, with a size of approximately 4.9 × 4.3 cm, left seminal vesicle compressed. DIAGNOSES: Prostatic synovial sarcoma (biphasic type) combined with prostatic acinar adenocarcinoma (Gleason 3 + 3). INTERVENTION: The patient received radical prostatectomy, followed by adjuvant chemotherapy and radiotherapy. OUTCOME: After 2 months of follow-up, at the time of writing this article, the patient received a comprehensive treatment plan of adjuvant chemotherapy and radiotherapy for 2 months, and no recurrence or metastasis was found. LESSONS: Primary prostatic synovial sarcoma (biphasic type) combined with prostatic acinar adenocarcinoma is a very unique and rare case, and effective treatment guidelines are not yet clear, posing new challenges to clinical treatment. Making full use of pathological and imaging examinations, early diagnosis and radical surgery combined with multidisciplinary treatment seem to be still a positive method.

Safety and Efficacy of NY-ESO-1 Antigen-Specific T-Cell Receptor Gene-Transduced T Lymphocytes in Patients with Synovial Sarcoma: A Phase I/II Clinical Trial.

PURPOSE: To determine, for patients with advanced or recurrent synovial sarcoma (SS) not suitable for surgical resection and resistant to anthracycline, the safety and efficacy of the infusion of autologous T lymphocytes expressing NY-ESO-1 antigen-specific T-cell receptor (TCR) gene and siRNA to inhibit the expression of endogenous TCR (product code: TBI-1301). PATIENTS AND METHODS: Eligible Japanese patients (HLA-A*02:01 or *02:06, NY-ESO-1-positive tumor expression) received cyclophosphamide 750 mg/m2 on days -3 and -2 (induction period) followed by a single dose of 5×109 (±30%) TBI-1301 cells as a divided infusion on days 0 and 1 (treatment period). Primary endpoints were safety-related (phase I) and efficacy-related [objective response rate (ORR) by RECIST v1.1/immune-related RECIST (irRECIST); phase II]. Safety- and efficacy-related secondary endpoints were considered in both phase I/II parts. RESULTS: For the full analysis set (N = 8; phase I, n = 3; phase II, n = 5), the ORR was 50.0% (95% confidence interval, 15.7-84.3) with best overall partial response in four of eight patients according to RECIST v1.1/irRECIST. All patients experienced adverse events and seven of eight patients (87.5%) had adverse drug reactions, but no deaths were attributed to adverse events. Cytokine release syndrome occurred in four of eight patients (50.0%), but all cases recovered with prespecified treatment. Immune effector cell-associated neurotoxicity syndrome, replication-competent retrovirus, and lymphocyte clonality were absent. CONCLUSIONS: Adoptive immunotherapy with TBI-1301 to selectively target NY-ESO-1-positive tumor cells appears to be a promising strategy for the treatment of advanced or recurrent SS with acceptable toxicity.

Sarcoma care in the era of precision medicine.

Sarcoma subtype classification is currently mainly based upon histopathological morphology. Molecular analyses have emerged as an efficient addition to the diagnostic workup and sarcoma care. Knowledge about the sarcoma genome increases, and genetic events that can either support a histopathological diagnosis or suggest a differential diagnosis are identified, as well as novel therapeutic targets. In this review, we present diagnostic, therapeutic, and prognostic molecular markers that are, or might soon be, used clinically. For sarcoma diagnostics, there are specific fusions highly supportive or pathognomonic for a diagnostic entity-for instance, SYT::SSX in synovial sarcoma. Complex karyotypes also give diagnostic information-for example, supporting dedifferentiation rather than low-grade central osteosarcoma or well-differentiated liposarcoma when detected in combination with MDM2/CDK4 amplification. Molecular treatment predictive sarcoma markers are available for gastrointestinal stromal tumor (GIST) and locally aggressive benign mesenchymal tumors. The molecular prognostic markers for sarcomas in clinical practice are few. For solitary fibrous tumor, the type of NAB2::STAT6 fusion is associated with the outcome, and the KIT/PDGFRA pathogenic variant in GISTs can give prognostic information. With the exploding availability of sequencing technologies, it becomes increasingly important to understand the strengths and limitations of those methods and their context in sarcoma diagnostics. It is reasonable to believe that most sarcoma treatment centers will increase the use of massive-parallel sequencing soon. We conclude that the context in which the genetic findings are interpreted is of importance, and the interpretation of genomic findings requires considering tumor histomorphology.

Intrathoracic synovial sarcoma with BRAF V600E mutation.

We report a case of 15-year-old boy with intrathoracic synovial sarcoma who relapsed after standard chemotherapy, surgery and radiotherapy. The molecular analysis of the tumour identified a BRAF V600E mutation at time of progression of relapsed disease under third line systemic treatment. This mutation is commonly seen in melanomas and papillary thyroid cancers, but less prevalent (typically <5%) across a variety of other cancer types. The patient underwent selective BRAF inhibitor Vemurafenib treatment achieving partial response (PR) with a progression free survival (PFS) ratio of 1.6 months and an overall survival of 19 months, alive in continuous PR. This case highlights the role of routinely next generation sequencing (NGS) used to drive treatment choice and to investigate extensively synovial sarcoma tumour for BRAF mutation.

Treatment patterns and outcomes in patients with metastatic synovial sarcoma in France, Germany, Italy, Spain and the UK.

Aim: Describing the treatment patterns, outcomes by line of treatment (LOT), and healthcare resource utilization (HCRU) in patients with metastatic synovial sarcoma (mSS). Patients & methods: In this descriptive, non-interventional, retrospective cohort study, physicians from five European countries reported on patients with recent pharmacological treatment for mSS. Results: Among 296 patients with mSS, 86.1, 38.9 and 8.4% received 1 LOT (1L), 2 LOTs (2L) and 3+ LOTs (L3+), respectively. Common regimens were doxorubicin/ifosfamide-based (37.4%) for 1L and trabectedin-based for 2L (29.7%). For 1L, median time to next treatment was 13.1 and 6.0 months for living and deceased patients, respectively. Median OS was 22.0, 6.0 and 4.9 months in all patients, 2L and 3L, respectively. HCRU data showed median one inpatient hospital admission, 3 days in hospital and four outpatient visits yearly. Conclusion: This large-scale study documents high unmet needs in patients previously treated for mSS and for more effective therapies.

Localized Synovial Sarcoma: A Population-Based Analysis of Treatment Patterns and Survival.

Purpose: Synovial sarcoma (SS) is a rare, high-grade soft tissue tumor that requires multidisciplinary and multimodal care with surgery, radiotherapy, and chemotherapy. We examined the impact of sociodemographic and clinical factors on treatment patterns and survival in localized SS patients. Methods: Adolescents and young adults (AYAs, 15-39 years) and older adults ("adults," ≥40 years) diagnosed with localized SS from 2000 to 2018 were identified in the California Cancer Registry. Multivariable logistic regression identified clinical and sociodemographic factors associated with receipt of chemotherapy and/or radiotherapy. Cox proportional hazards regression identified factors associated with overall survival (OS). Results are reported as odds ratios (ORs) and hazard ratios (HRs), respectively, with 95% confidence intervals (CIs). Results: More AYAs (n = 346) than adults (n = 272) received chemotherapy (47.7% vs. 36.4%) and radiotherapy (62.1% vs. 58.1%). Age at diagnosis, tumor size, treatment at National Cancer Institute-Children's Oncology Group (NCI-COG)-designated facilities, insurance status, and neighborhood socioeconomic status (SES) influenced treatment patterns. Among AYAs, treatment at NCI-COG-designated facilities was associated with receiving chemotherapy (OR 2.74, CI 1.48-5.07) and low SES was associated with worse OS (HR 2.28, 1.09-4.77). In adults, high SES was associated with receiving chemoradiotherapy (OR 3.20, CI 1.40-7.31), whereas public insurance was associated with decreased odds of chemoradiotherapy (OR 0.44, CI 0.20-0.95). With regard to treatment, absence of radiotherapy (HR 1.94, CI 1.18-3.20) was associated with worse OS in adults. Conclusion: In localized SS, both clinical and sociodemographic factors influenced treatment patterns. Further research should investigate how SES-related factors produce treatment disparities and identify interventions to improve treatment equity and outcomes.

Relapsed Synovial Sarcoma: Treatment Options.

OPINION STATEMENT: Synovial sarcoma (SS) is a fusion-driven subtype of sarcoma that is a more chemo-sensitive subtype of soft tissue sarcoma. While chemotherapy options are currently standard of care, our fundamental understanding of the biology of SS is driving new therapies. We will review the current standard of care, as well as the current therapies showing promise in a clinical trial. It is our hope that by encouraging participation in clinical trials, the fundamental therapies available for SS will change the current treatment paradigm.

Blue light induces apoptosis and autophagy by promoting ROS-mediated mitochondrial dysfunction in synovial sarcoma.

BACKGROUND: Synovial sarcoma (SS) has limited treatment options and there is an urgent need to develop a novel therapeutic strategy to treat SS. Blue light (BL) has been shown to inhibit the growth of several cancer cells. However, the efficacy of BL in soft tissue sarcomas such as SS has not been demonstrated, and the detailed mechanism underlying the antitumor activity of BL is not fully understood. In this study, we investigated the antitumor effect of BL on SS. METHODS: Human SS cell lines were continuously irradiated with BL using light-emitting diodes (LEDs) in an incubator for in vitro analysis. The chicken chorioallantoic membrane (CAM) tumors and xenograft tumors in mice were subjected to daily BL irradiation with LEDs. RESULTS: BL caused growth inhibition of SS cells and histological changes in CAM tumors. BL also suppressed the migration and invasion abilities of SS cells. The type of cell death in SS cells was revealed to be apoptosis. Furthermore, BL induced excessive production of reactive oxygen species (ROS) in mitochondria, resulting in oxidative stress and malfunctioned mitochondria. Reducing the production of ROS using N-acetylcysteine (NAC), a ROS scavenger, attenuated the inhibitory effect of BL on SS cells and mitochondrial dysfunction. In addition, BL induced autophagy, which was suppressed by the administration of NAC. The autophagy inhibitor of 3-methyladenine and small interfering RNA against the autophagy marker light chain 3B facilitated apoptotic cell death. Moreover, BL suppressed tumor growth in a mouse xenograft model. CONCLUSION: Taken together, our results revealed that BL induced apoptosis via the ROS-mitochondrial signaling pathway, and autophagy was activated in response to the production of ROS, which protected SS cells from apoptosis. Therefore, BL is a promising candidate for the development of an antitumor therapeutic strategy targeting SS.

A phase 1 trial of NY-ESO-1-specific TCR-engineered T-cell therapy combined with a lymph node-targeting nanoparticulate peptide vaccine for the treatment of advanced soft tissue sarcoma.

The efficacy of immune checkpoint inhibitors is limited in refractory solid tumors. T-cell receptor gene-modified T (TCR-T)-cell therapy has attracted attention as a new immunotherapy for refractory cold tumors. We first investigated the preclinical efficacy and mode of action of TCR-T cells combined with the pullulan nanogel:long peptide antigen (LPA) vaccine in a mouse sarcoma model that is resistant to immune checkpoint inhibition. Without lymphodepletion, the pullulan nanogel:LPA vaccine markedly increased the number of TCR-T cells in the draining lymph node and tumor tissue. This change was associated with enhanced CXCR3 expression in TCR-T cells in the draining lymph node. In the phase 1 trial, autologous New York esophageal squamous cell carcinoma 1 (NY-ESO-1)-specific TCR-T cells were infused twice into HLA-matched patients with NY-ESO-1+ soft tissue sarcoma (STS). The pullulan nanogel:LPA vaccine contains an epitope recognized by TCR-T cells, and it was subcutaneously injected 1 day before and 7 days after the infusion of TCR-T cells. Lymphodepletion was not performed. Three patients with refractory synovial sarcoma (SS) were treated. Two out of the three patients developed cytokine release syndrome (CRS) with low-to-moderate cytokine level elevation. We found obvious tumor shrinkage lasting for more than 2 years by tumor imaging and long-term persistence of TCR-T cells in one patient. In conclusion, NY-ESO-1-specific TCR-T-cell therapy plus vaccination with the pullulan nanogel carrying an LPA containing the NY-ESO-1 epitope without lymphodepletion is feasible and can induce promising long-lasting therapeutic effects in refractory SS (Registration ID: JMA-IIA00346).

A review on pulmonary and mediastinal synovial sarcoma.

Sarcoma is defined as a tumor located in the thoracic cavity. However, sarcoma can occur on every side of the body. Synovial sarcoma is a rare soft tissue tumor originating from pluripotent with a high malignancy rate. The most common predilection of synovial sarcoma is in the joints. Primary synovial sarcoma of the lung and mediastinum are rare tumors and generally malignant. There are only a few cases have been reported. Definite diagnosis is made by histopathological, immunohistochemistry, and cytogenetic examination. The management strategy for synovial sarcoma requires multimodality treatment with surgery, chemotherapy, and radiotherapy. However, effective and relatively non-toxic therapy for primary synovial sarcoma is still developed. The five years life expectancy is higher if the patient received adjuvant radiotherapy and/or chemotherapy after surgery.

Synovial sarcoma with intra-abdominal metastasis causing hemoperitoneum: a case-report.

Synovial sarcoma is a rare soft tissue sarcoma which frequently involves the upper or lower extremities. Soft tissue sarcomas including synovial sarcoma have a propensity to metastasize to the lungs, and there are very few reports of metastatic lesions in other locations.Here, we report a case of a 49-year-old patient who underwent neoadjuvant chemoradiation for an upper extremity synovial sarcoma and presented approximately 4 years later with abdominal pain and hemoperitoneum and was ultimately found to have metastatic synovial sarcoma involving the greater curvature of the stomach and surrounding peri-gastric soft tissue. We describe the multidisciplinary management of this complex patient presentation and propose that expanded surveillance imaging beyond that of the local tumor resection bed and the chest may be beneficial especially in tumors with high-risk features.

Derivation and validation of a risk classification tree for patients with synovial sarcoma.

BACKGROUND: Synovial sarcoma (SS) accounts for 8%-10% of all soft-tissue sarcomas. Clinical presentation and outcomes vary, yet discrete risk groups based on validated prognostic indices are not defined for the full spectrum of patients with SS. METHODS: We performed a retrospective cohort study using data from the SEER (surveillance, epidemiology, and end results program) database of SS patients who were <70 years of age at diagnosis. We constructed a recursive partitioning model of overall survival using a training cohort of 1063 patients with variables: Age at diagnosis, sex, race, ethnicity, primary site, tumor size, tumor grade, and stage. Based on this model, we grouped patients into three risk groups and estimated 5-year overall survival for each group. We then applied these groups to a test cohort (n = 1063). RESULTS: Our model identified three prognostic groups with significantly different overall survival: low risk (local/regional stage with either <21 years of age OR tumor <7.5 cm and female sex), intermediate-risk (local/regional stage, age ≥ 21 years with either male sex and tumor <7.5 cm OR any sex with appendicular anatomic location) and high risk (local/regional stage, age ≥ 21 years, tumor size ≥7.5 cm and non-appendicular location OR distant stage). Prognostic groups were applied to the test cohort, showing significantly different survival between groups (p < 0.0001). CONCLUSIONS: Our analysis yields an intuitive risk-classification tree with discrete groups, which may provide useful information for researchers, patients, and clinicians. Prospective validation of this model may inform efforts at risk-stratifying treatment.

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.

Biomarker correlates with response to NY-ESO-1 TCR T cells in patients with synovial sarcoma.

Autologous T cells transduced to express a high affinity T-cell receptor specific to NY-ESO-1 (letetresgene autoleucel, lete-cel) show promise in the treatment of metastatic synovial sarcoma, with 50% overall response rate. The efficacy of lete-cel treatment in 45 synovial sarcoma patients (NCT01343043) has been previously reported, however, biomarkers predictive of response and resistance remain to be better defined. This post-hoc analysis identifies associations of response to lete-cel with lymphodepleting chemotherapy regimen (LDR), product attributes, cell expansion, cytokines, and tumor gene expression. Responders have higher IL-15 levels pre-infusion (p = 0.011) and receive a higher number of transduced effector memory (CD45RA- CCR7-) CD8 + cells per kg (p = 0.039). Post-infusion, responders have increased IFNγ, IL-6, and peak cell expansion (p < 0.01, p < 0.01, and p = 0.016, respectively). Analysis of tumor samples post-treatment illustrates lete-cel infiltration and a decrease in expression of macrophage genes, suggesting remodeling of the tumor microenvironment. Here we report potential predictive and pharmacodynamic markers of lete-cel response that may inform LDR, cell dose, and strategies to enhance anticancer efficacy.

New benchmarks to design clinical trials with advanced or metastatic liposarcoma or synovial sarcoma patients: An EORTC - Soft Tissue and Bone Sarcoma Group (STBSG) meta-analysis based on a literature review for soft-tissue sarcomas.

BACKGROUND: Recently, we performed a meta-analysis based on a literature review for STS trials (published 2003-2018, ≥10 adult patients) to update long-standing reference values for leiomyosarcomas. This work is extended for liposarcomas (LPS) and synovial sarcomas (SS). MATERIALS AND METHODS: Study endpoints were progression-free survival rates (PFSRs) at 3 and 6 months. Trial-specific estimates were pooled per treatment line (first-line or pre-treated) with random effects meta-analyses. The choice of the therapeutic benefit to target in future trials was guided by the European Society for Medical Oncology Magnitude of Clinical Benefit Scale (ESMO-MCBS). RESULTS: Information was acquired for 1030 LPS patients (25 trials; 7 first-line, 17 pre-treated, 1 both) and 348 SS patients (13 trials; 3 first-line, 10 pre-treated). For LPS, the overall pooled first-line PFSRs were 69% (95%-CI 60-77%) and 56% (95%-CI 45-67%) at 3 and 6 months, respectively. These rates were 49% (95%-CI 40-57%)/28% (95%-CI 22-34%) for >1 lines. For SS, first-line PFSRs were 74% (95%-CI 58-86%)/56% (95%-CI 31-78%) at 3 and 6 months, and pre-treated rates were 45% (95%-CI 34-57%)/25% (95%-CI 16-36%). Following ESMO-MCBS guidelines, the minimum values to target are 79% and 69% for first-line LPS (82% and 69% for SS) at 3 and 6 months. For pre-treated LPS, recommended PFSRs at 3 and 6 months suggesting drug activity are 63% and 44% (60% and 41% for SS). CONCLUSIONS: New benchmarks are proposed for advanced/metastatic LPS or SS to design future histology-specific phase II trials. More data are needed to provide definitive thresholds for the different LPS subtypes.

Treatment patterns and outcomes in metastatic synovial sarcoma: a real-world study in the US oncology network.

Aim: To examine and understand patient characteristics, treatment patterns and outcomes for patients with metastatic synovial sarcoma (mSS) treated in a US community setting. Materials & methods: Retrospective observational study in adults with mSS in The US Oncology Network (diagnosed January 2012-December 2018). Results: Of 202 patients diagnosed with synovial sarcoma (SS), 71 had mSS. Of 39 patients with mSS who received first-line (1L) systemic treatment, 25 and 16 continued to 2L and 3L+ treatment, respectively. With each subsequent treatment line, time-to-treatment-discontinuation (1L-3L: 3.9-2.7 months) and time-to-next-treatment (1L-3L: 9.3-4.6 months) decreased. At 1L, median overall survival was 24.5 months. Conclusion: This study highlights the ongoing need for effective therapies for mSS.

Synovial sarcoma (SS) is a rare and aggressive type of soft tissue sarcoma (STS), a group of rare cancers that start in the soft tissues, such as muscle, tendons, fat, lymph and blood vessels and nerves. Usually STS presents in one location, and frequently spreads to other locations, referred to as metastatic SS (mSS). Many studies have explored the characteristics, treatments and outcomes of people with STS. Yet, a limited number of studies have been performed specifically for people with mSS. This study aims to describe characteristics, treatment patterns and clinical outcomes of people with mSS treated in a US community setting. The study showed that more than a third of people diagnosed with SS had disease that spread, mostly to the lung. Of the 71 people with mSS included in the analysis, 39 people received chemotherapy. Of these, 25 people with mSS needed second-line chemotherapy and a further 16 people with mSS required third-line treatment. People with mSS who did not respond well to chemotherapy received a variability of treatments in the US community setting. More lines of treatment were associated with shorter time-to-next-treatment and reduced survival time. Together, these findings highlight the burden of illness and the need for more effective treatments for people with this rare disease. Investigating the characteristics, treatment patterns and clinical outcomes of people with mSS can help to understand the unmet need in this population and pave the way to improving future treatment approaches.