Systemic treatment of advanced clear cell sarcoma: results from a retrospective international series from the World Sarcoma Network

Background

Clear cell sarcoma (CCS) is a translocated aggressive malignancy with a high incidence of metastases and poor prognosis. There are few studies describing the activity of systemic therapy in CCS. We report a multi-institutional retrospective study of the outcomes of patients with advanced CCS treated with systemic therapy within the World Sarcoma Network (WSN).

Materials and methods

Patients with molecularly confirmed locally advanced or metastatic CCS treated with systemic therapy from June 1985 to May 2021 were included. Baseline demographic and treatment information, including response by Response Evaluation Criteria in Solid Tumours (RECIST) 1.1, was retrospectively collected by local investigators. Descriptive statistics were carried out.

Results

Fifty-five patients from 10 institutions were included. At diagnosis, the median age was 30 (15-73) years and 24% (n = 13/55) had metastatic disease. The median age at diagnosis was 30 (15-73) years. Most primary tumours were at aponeurosis (n = 9/55, 16%) or non-aponeurosis limb sites (n = 17/55, 31%). The most common fusion was EWSR1–ATF1 (n = 24/55, 44%). The median number of systemic therapies was 1 (range 1-7). The best response rate was seen for patients treated with sunitinib (30%, n = 3/10), with a median progression-free survival of 4 [95% confidence interval (CI) 1-7] months. The median overall survival for patients with advanced/metastatic disease was 15 months (95% CI 3-27 months).

Conclusions

Soft tissue sarcoma-type systemic therapies have limited benefit in advanced CCS and response rate was poor. International, multicentre prospective translational studies are required to identify new treatments for this ultra-rare subtype, and access to early clinical trial enrolment remains key for patients with CCS.

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This is the largest reported series of advanced CCS patients treated with systemic therapy.

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The activity of sarcoma-type systemic therapy is poor and modest responses were seen only with sunitinib.

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Effective therapies are needed to improve outcomes for patients with this ultra-rare sarcoma type.

Update on Systemic Therapy for Advanced Soft Tissue Sarcoma

Background: Soft tissue sarcoma (STS) is a rare group of mesenchymal neoplasms which contains over 50 heterogenous subtypes.  There have been great efforts to increase the understanding of treatment of advanced STS (unresectable or metastatic disease). We wished to determine if outcomes for patients with advanced STS have improved over time, and to assess the current evidence for systemic therapy. Methods: We performed a scoping review to evaluate the contemporary evidence for systemic treatment of advanced soft tissue in adults (>18 years old). Phase I, II, and III studies of systemic therapy for advanced STS published in the English language were included. After abstract and full text review of 77 studies, 62 trials met inclusion criteria.  Results: The number of clinical trials conducted and published in advanced STS has increased over the last 30 years. Although median OS has increased, attempts at improving first line therapy through dose intensification, doublet chemotherapy or alternative backbones have not been successful. The optimal therapy beyond anthracyclines remains a challenge, especially given the inherent heterogeneity of grouping multiple STS subtypes within clinical trials. However, increasing numbers of agents are being studied and several studies had shown isolated PFS or OS benefit.  Conclusions: First line anthracycline systemic therapy remains the standard of care for advanced STS.  However, choice of subsequent therapy beyond anthracyclines remains challenging. Novel systemic therapies, using molecular diagnostics to direct therapy, subtype specific trials and learning from real world retrospective data are all important in improving outcomes for patients with advanced STS.

Update on systemic therapy for advanced soft-tissue sarcoma

Background

Soft-tissue sarcoma (sts) represents a rare group of mesenchymal neoplasms comprising more than 50 heterogeneous subtypes. Great efforts have been made to increase the understanding of the treatment of advanced sts (unresectable or metastatic disease). We set out to determine whether outcomes for patients with advanced sts have improved over time and to assess the current evidence for systemic therapy.

Methods

In a scoping review, we evaluated the contemporary evidence for systemic treatment of advanced sts in adults (>18 years of age). Phase i, ii, and iii studies of systemic therapy for advanced sts published in the English language were included. After abstract and full-text review of seventy-seven studies, sixty-two trials met the inclusion criteria.

Results

The number of clinical trials conducted and published in advanced sts has increased over the last 30 years. Although median overall survival has increased, attempts at improving first-line therapy through dose intensification, doublet chemotherapy, or alternative backbones have not been successful. The optimal therapy beyond anthracyclines remains a challenge, especially given the heterogeneity that grouping multiple sts subtypes within clinical trials creates. However, increasing numbers of agents are being studied, and several studies had shown isolated benefit in progression-free or overall survival.

Summary

First-line systemic therapy with an anthracycline remains the standard of care for advanced sts. However, choice of subsequent therapy beyond anthracyclines remains challenging. Novel systemic therapies, use of molecular diagnostics to direct therapy, subtype-specific trials, and learnings from real-world retrospective data are all important for improving outcomes in patients with advanced sts.