Gemcitabine and docetaxel in patients with unresectable leiomyosarcoma: results of a phase II trial.

Few chemotherapy agents are active in leiomyosarcoma (LMS), particularly LMS that has progressed after doxorubicin treatment. We sought to determine the response to gemcitabine plus docetaxel among patients with LMS. Patients with unresectable LMS of uterine (n = 29) or other (n = 5) primary sites who did not respond to zero to two prior chemotherapy regimens were enrolled onto a phase II study of gemcitabine 900 mg/m(2) intravenously (i.v.) on days 1 and 8 plus docetaxel 100 mg/m(2) i.v. on day 8 with granulocyte colony-stimulating factor given subcutaneously on days 9 to 15, delivered every 21 days. Patients with prior pelvic radiation received 25% lower doses of both agents. Gemcitabine was delivered over 30 or 90 minutes in cycles 1 and 2 and by 90-minute infusion in all subsequent cycles. Pharmacokinetic studies assessed in vivo differences in gemcitabine concentrations with different rates of infusion. Thirty-four patients (median age, 55 years; range, 32 to 74 years) have enrolled. Fourteen had received prior pelvic radiation. Sixteen of 34 patients had progressed after doxorubicin-based therapy; 18 had no prior chemotherapy. Among 34 patients, complete response was observed in three patients and partial response in 15, for an overall response rate of 53% (95% confidence interval, 35% to 70%). Seven patients had stable disease. Fifty percent of patients previously treated with doxorubicin responded. Hematologic toxicity was common (neutropenia: grade 3, 15%; grade 4, 6%; thrombocytopenia: grade 3, 26%; grade 4, 3%), but neutropenic fever (6%) and bleeding events (0%) were rare. The median time to progression was 5.6 months (range, 4 to 10 months). Gemcitabine plus docetaxel is tolerable and highly active in treated and untreated patients with LMS.