Relapse in synovial sarcoma: what can be done for poor outcomes?

Abstract

Improving patients’ chances of cure after their tumors have relapsed is one of the greatest challenges oncologists face, especially when it comes to patients whose front-line treatment had already included both chemotherapy and radiotherapy. It is almost as if oncologists had just one shot to fire in their battle against cancer, no second chances. Once standard chemotherapy has failed, cancer clone cells are likely to develop multidrug resistance, becoming insensitive to any further systemic therapy. Likewise, reirradiation after local relapse within previous radiation fields is rarely feasible and, even when it can be attempted, it is usually to no effect. Synovial sarcoma is a good example to discuss in this scenario. It is a typical tumor spanning the pediatric and adult age groups [1]. This highgrade soft tissue sarcoma carries a good overall prognosis – approximately three in four patients are cured nowadays – generally depending on the feasibility of surgical resection, the tumor’s size and site, and any presence of metastases [1–4]. As in other tumor types however, studies on synovial sarcoma have reported a narrow ‘salvage gap’, definable as the difference between event-free survival and overall survival. This is tantamount to saying that the chances of further treatments curing patients who progress or relapse are decidedly slim. A recent Italian pediatric study described the pattern of synovial sarcoma recurrence and the prognostic variables influencing survival with a view of finding a risk-adapted stratification procedure that could facilitate the planning of second-line therapies [5]. If we could distinguish between patients who have realistic prospects of cure with currently available treatment options and those unlikely to benefit from them, then the latter might, in principle, be offered experimental therapies. Most of the relapses in the pediatric sample considered were metastatic (particularly to the lung), and 10-year survival after relapsing was 21% [5]. The final outcome was influenced Andrea Ferrari* & Michela Casanova Editorial