Neoadjuvant Capecitabine/Temozolomide for Locally Advanced or Metastatic Pancreatic Neuroendocrine Tumors.

Abstract

The combination chemotherapy regimen capecitabine/temozolomide (CAPTEM) is efficacious for metastatic well-differentiated pancreatic neuroendocrine tumors (PNETs), but its role in the neoadjuvant setting has not been established. The outcomes of all patients with locally advanced or resectable metastatic PNETs who were treated with neoadjuvant CAPTEM between 2009 and 2017 at 2 high-volume institutions were retrospectively reviewed. Thirty patients with locally advanced PNET (n = 10) or pancreatic neuroendocrine hepatic metastases (n = 20) received neoadjuvant CAPTEM. Thirteen patients (43%) exhibited partial radiographic response (PR), 16 (54%) had stable disease, and 1 (3%) developed progressive disease. Twenty-six (87%) patients underwent resection (pancreatectomy [n = 12], combined pancreatectomy and liver resection [n = 8], or major hepatectomy alone [n = 6]); 3 (18%) declined surgery despite radiographic PR, and 1 (3%) underwent aborted pancreatoduodenectomy. Median primary tumor size was 5.5 cm, and median Ki-67 index was 3.5%. Rates of PR were similar across tumor grades (P = 0.24). At median follow-up of 49 months, median progression-free survival was 28.2 months and 5-year overall survival was 63%. Neoadjuvant CAPTEM is associated with favorable radiographic objective response rates for locally advanced or metastatic PNET and may facilitate selection of patients appropriate for surgical resection.