Phase II clinical trial of neoadjuvant trabectedin in patients with advanced localized myxoid liposarcoma

To evaluate neoadjuvant trabectedin (1.5 mg/m(2) 24-h i.v. infusion every 3 weeks; three to six cycles) in patients with locally advanced myoxid liposarcoma (ML) previously untreated with chemotherapy or radiation.

Primary efficacy end point was pathological complete response (pCR) or tumoral regression rate. Objective response according to RECIST (v.1.0) was a secondary end point.

Three of 23 assessable patients had pCR [13%; 95% confidence interval (CI), 3% to 34%]. Furthermore, very good and moderate histological responses were observed in another 2 and 10 patients, respectively. Histological decrement in the cellular and vascular tumor component and maturation of tumor cells to lipoblasts were observed in both myoxid and myoxid/round cell variants. Seven patients had partial response according to RECIST (objective response rate of 24%; 95% CI, 10% to 44%). No disease progression was reported. Neoadjuvant trabectedin was usually well tolerated, with a safety profile similar to that described in patients with soft tissue sarcoma or other tumor types.

Trabectedin 1.5 mg/m(2) given as a 24-h i.v. infusion every 3 weeks is a therapeutic option in the neoadjuvant setting of ML.