First-Line Treatment of Metastatic Pancreatic Endocrine Carcinomas With Capecitabine and Temozolomide

Abstract

Background: Temozolomide is an active agent in metastatic pancreatic endocrine carcinomas. In-vitro data indicates that the combination of capecitabine and temozolomide is synergistic for induction of apoptosis in neuroendocrine tumor cell lines. We evaluated the efficacy of capecitabine and temozolomide in 33 patients with metastatic pancreatic endocrine carcinomas to assess response rate, progression free survival (PFS) and overall survival (OS). Methods: Patients with metastatic, differentiated pancreatic endocrine carcinomas who had not received prior systemic chemotherapy were treated with capecitabine 750 mg/m2 twice daily days 1-14 and temozolomide 200 mg/m2 once daily days 10-14 every 28 days. Response rates were assessed by RECIST criteria. Results: Among 33 patients treated, 22 (67%) patients achieved an objective radiographic response. Median progression-free survival was 18 months. The rate of survival at two years was 92%. Only four patients (12%) experienced grade 3 or 4 adverse events. Conclusion: The combination of capecitabine and temozolomide is associated with an exceptionally high and durable response rate in metastatic endocrine carcinomas of the pancreas. Clinical endpoints, including response rate, survival and toxicity, are superior to those observed with streptozocin-based regimens.