A phase II trial of temozolomide as a 6-week, continuous, oral schedule in patients with advanced soft tissue sarcoma: a study by the Spanish Group for Research on Sarcomas.

BACKGROUND: The objective of this study was to evaluate the activity and toxicity of temozolomide given as an extended schedule in patients with advanced sarcoma.
METHODS: Forty-nine patients with pretreated soft tissue sarcoma (the STS arm) and 18 patients with previously untreated gastrointestinal stromal tumor (the GIST arm) were enrolled onto a 2-arm, multicenter, Phase II study between November 1999 and July 2001. Temozolomide was administered on a 6-week, continuous, oral schedule at a dose of 75 mg/m2 per day in 41 patients and, after an amendment, at a dose of 100 mg/m2 per day in 22 patients.
RESULTS: Among 45 eligible patients in the STS arm, there were 7 partial responses, for an overall response rate of 15.5% (95% confidence interval [95% CI], 5-26%). Responses were seen in 5 of 11 patients who had gynecologic leiomyosarcoma. The median response duration was 12.5 months (range, 3.9-58.0 mos). In 4 patients, response lasted > 1 year, and 2 of those patients remained progression free for > 3 years. The median time to progression was 2.2 months (95% CI, 1.8-2.5 mos), and the median overall survival was 8.1 months (95% CI, 5.6-10.6 mos). Progression-free survival rates at 3 months and 6 months were 39.5% and 26%, respectively. In the GIST arm, no responses were noted. Grade 3-4 granulocytopenia, thrombocytopenia, and anemia were observed in 6 patients, 5 patients, and 7 patients, respectively. The most common nonhematologic toxicities were emesis and fatigue.
CONCLUSIONS: Temozolomide at the extended schedule was tolerated well and had activity in patients with pretreated soft tissue sarcomas, and especially among patients with gynecologic leiomyosarcoma. Copyright 2005 American Cancer Society