Phase II trial of neoadjuvant temozolomide in resectable melanoma patients

Abstract

Background: We treated melanoma patients with temozolomide (TMZ) in the neoadjuvant setting and collected cryopreserved tumor samples before and after treatment. The primary objective was to determine whether the response proportion was higher than previously reported in widely metastatic patients. A secondary objective was to test the feasibility of obtaining adequate tissue before and after treatment for genetic testing.

Materials and methods: Chemotherapy-naive melanoma patients who were candidates for surgical resection were eligible. TMZ was administered orally at 75 mg/m(2)/day for 6 weeks of every 8-week cycle. Cycles were repeated until complete response (CR), progression, or stable disease (SD) for two cycles.

Results: Of 19 assessable patients, 2 had CRs and 1 had partial response. Four patients had SD; 12 progressed. Tumor O-6-methylguanine-DNA methyltransferase (MGMT) promoter was unmethylated in all nine patients analyzed including from the two CR patients. Pretreatment tumor microarray results were obtained in 16 of 19 patients.

Conclusions: The response proportion to TMZ in the neoadjuvant setting was 16%, not different than in the metastatic setting. Responses were seen even in tumors with a methylated MGMT promoter. Pretreatment cryopreserved tumor adequate for microarray analysis could be obtained in most, but not all, patients. Post-treatment tumor was unavailable in complete responders.