Author(s): Elizabeth J. Davis, Rashmi Chugh, Shreyaskumar Patel, Scott Schuetze; University of Michigan, Ann Arbor, MI; University of Michigain Health System, Ann Arbor, MI; The University of Texas MD Anderson Cancer Center, Houston, TXAbstract Disclosures
Abstract:
Background: Treating STS with systemic therapy beyond six months is challenging due to cumulative toxicity. Trabectedin (T) has demonstrated efficacy and tolerability in STS and became available in 2005 through an expanded access program (EAP).
Results of the EAP noted better overall survival and response rates in patients (pts) with leiomyosarcoma (LMS) and liposarcoma (LPS) compared to other histologies. Multiple cycles of T were tolerable with 30% of pts receiving ≥ 6 cycles and 7% of pts receiving ≥ 1 year of therapy, but descriptions of pts receiving T beyond one year are limited.
Methods: We performed a retrospective analysis of pts with STS at the University of Michigan and M.D. Anderson Cancer Center who received long-term (≥ 10 cycles) T. We further subdivided pts into those treated for more than one year (≥ 18 cycles) and two years (≥ 35 cycles). Variables evaluated included age, gender, histology, site of primary tumor, number of prior treatments, number of dose reductions, and reason for discontinuation of T.
Results: Four hundred and twenty-two pts treated with T were identified. Sixty-two pts (15%) received ≥ 10 cycles; 95% of these pts were treated on the EAP. Twenty-two pts (5%) were treated for ≥ 1 year and seven pts (2%) for ≥ 2 years. All pts treated for ≥ 1 year had LMS or LPS. Five pts (23%) treated for ≥ 1 year did not require a dose reduction. The primary reason for discontinuation of T was sarcoma progression.
Conclusions: Trabectedin is a tolerable long-term therapy for a subset of pts with STS. Pts with LMS and LPS may derive the most benefit from long-term treatment, but further study is needed in a larger number of pts.
Clinically relevant toxicities leading to T discontinuation beyond 1 year were fatigue and myelosuppression.