A phase II trial of piroxantrone in endometrial cancer: Southwest Oncology Group study 8918.

A phase II trial of the new anthrapyrazole piroxantrone was carried out by the Southwest Oncology Group in patients with advanced metastatic or recurrent endometrial cancer. A two-stage statistical design targeted accrual of 20 eligible patients. The starting dose of piroxantrone was 150 mg/m2 in patients without prior radiation therapy (RT) and 120 mg/m2 in patients with prior RT. There were 15 eligible patients, six of whom had received prior hormonal therapy while nine patients had not received prior hormonal therapy. Eight patients had received prior RT while seven patients had not received any prior RT. One to seven cycles of piroxantrone were administered. Dose escalation was feasible in four patients. No grade 5 toxicity was experienced by any patients. Most of the grade 4 (granulocytopenia in one) and grade 3 (leukopenia in three, granulocytopenia in three, anemia in two and thrombocytopenia in one) toxicity was related to myelosuppression. Grade 3 non-hematologic toxicities were nausea, fatigue and SGOT elevation. There was one partial response for a response rate of 7% (95% CI 0.2-32%) and median survival was 11 months (95% CI 3-13 months). The study was prematurely terminated due to lack of patient accrual.