Use of first-line trabectedin in advanced leiomyosarcoma: a review of clinical data and future perspectives

Abstract

Leiomyosarcomas (LMS) represent a large subgroup of soft-tissue sarcoma (STS) generally considered moderately sensitive to conventional chemotherapy. Single-agent doxorubicin is the standard first-line therapy for advanced non-selected STS, although combination with ifosfamide appears to be superior in terms of objective response. Gemcitabine-based regimes, dacarbazine, trabectedin and pazopanib seem to be especially active in patients with advanced LMS, while the activity of ifosfamide in this histotype is low. Data derived from clinical trials and retrospective series show that trabectedin is especially active in L-sarcomas including non-gynecological and uterine LMS as well as liposarcomas, in particular myxoid liposarcomas. Trabectedin has also been tested in the first-line setting, alone or in combination with doxorubicin, for the treatment of LMS of uterine and non-uterine origin in a trial by the French Sarcoma Group (phase II study LMS-02) with encouraging results in terms of median progression-free survival and objective response. The toxicity profile of trabectedin appears to be comparable to, or even more manageable than, that of other chemotherapy combinations in the first-line setting. Designing new clinical trials based on specific histologic subtypes is feasible, and the results of such studies would help to optimize the management of patients with STS.