Temozolomide: A Safe and Effective Treatment for Malignant Digestive Endocrine Tumors

Abstract

Background: Systemic chemotherapies are associated with limited response rates and significant toxicity in patients with malignant digestive endocrine tumors (DET). Preliminary studies have reported interesting results with temozolomide in patients with DET. Aim: It was the aim of this study to assess the efficacy and safety of temozolomide in patients with malignant DET. Patients and Methods: Twenty-one patients, median age 61 years (range 56–77), with metastatic well-differentiated DET were retrospectively studied. All patients except 1 had received prior treatment (hepatic resection, chemotherapy). All patients had progressive disease in the 3 months prior to entry into the study. Temozolomide was administered at doses of 200 mg/m² daily for 5 days, every 28 days. Treatment was assessed for safety, progression-free and overall survival. Results: The median number of temozolomide cycles was 5 (range 2–15). Grade 3 hematological toxicity occurred in 5 patients. There were no toxic deaths. According to the Response Evaluation Criteria in Solid Tumors criteria, partial response and stabilization were obtained in 1 (5%) and 17 patients (81%), respectively. The median time to progression was 9 months (range 3–26). The 1-year progression-free survival and overall survival were 42 and 77%, respectively. Conclusion: Temozolomide is a well-tolerated oral chemotherapy in patients with malignant DET, including those who have already received treatment. In patients with progressive disease, temozolomide controls tumor progression in 86% of cases.