Capecitabine and temozolomide for metastatic intermediate to high-grade pancreatic neuroendocrine neoplasm: a single center experience

BACKGROUND/AIMS: The combination of capecitabine and temozolomide (CAPTEM) is one of the treatment options for metastatic pancreatic neuroendocrine neoplasms (pNENs). This study aims to evaluate the efficacy of CAPTEM in patients with metastatic intermediate to high-grade pancreatic neuroendocrine tumor (pNET) or carcinoma (pNEC). METHODS: This study was conducted retrospectively in a single center. Patients were treated for intermediate to high-grade tumor with 750 mg/m(2) of capecitabine twice daily from day 1 to 14 and 200 mg/m(2) of temozolomide once daily from day 10 to 14, repeating twice in a cycle of 28 days. The primary outcomes were durations of overall survival (OS) and progression-free survival (PFS). The secondary outcomes consisted of objective response rate and disease control rate. RESULTS: A total of 12 patients (grade 2 NET in six, grade 3 NET in three, NEC in three patients) who received CAPTEM were included in this study. Patients received a median of five cycles (range, 2 to 46) of CAPTEM. The median dose combined 1,150 mg of capecitabine and 300 mg of temozolomide. The median OS and PFS were 41.2 months (range, 3.2 to 167) and 39.7 months (range, 2.1 to 100), respectively. Patients with NET had longer OS and PFS compared to those of patients with NEC (p = 0.002 and p = 0.028). High Ki-67 proliferative index (> 50%) was significantly associated with poor survival outcomes. CONCLUSIONS: CAPTEM showed favorable survival outcomes in patients with metastatic intermediate to high-grade pNENs. Our study supports that CAPTEM may be an effective treatment option for metastatic pNENs.