Multimodality management of borderline resectable pancreatic neuroendocrine tumors: Sentinel report of a single-institutional experience.

Abstract

418 Background: Pancreatic neuroendocrine tumors (PNET) constitute about 3% of pancreatic neoplasms. In borderline resectable disease, there is a lack of data to support an optimal neoadjuvant approach for curative outcomes. We describe our institutional experience with a multimodality approach. Methods: We identified all patients with borderline resectable PNET, using NCCN criteria for adenocarcinoma of the pancreas, who received neoadjuvant therapy at our institution between 2000 and 2013. The reason for borderline status was noted. Neoadjuvant regimen, radiographic response, pathologic response, surgical margins, nodal harvest, number of positive nodes, and recurrence were all documented. Results: A total of 112 patients had undergone pancreatic resections for neuroendocrine tumors during the study period. Six patients had borderline resectable disease. The mean age was 55 years (24-70). They all received at least 1 cycle of Temodar and Xeloda. Three of the six patients also received concurrent 5-FU and radiation. There was radiographic evidence of treatment response in all patients. Five of six patients (83 %) had negative margin (R0) resection. Low volume miliary metastatic disease in the liver was detected in 1 patient at the time of surgery. The median number of lymph nodes harvested was 12. Half of the patients had node positive disease. On pathologic review, 4 patients had histologic evidence of a moderate response. All patients are alive and 5/6 are free of disease. Range of follow up is 3.0-4.32 years. The patient with metastatic disease has had no progression and is the only one who is currently receiving any form of treatment. Conclusions: Neoadjuvant Temodar and Xeloda ± radiation with 5-FU sensitization can lead to R0 resection with durable response in patients with borderline resectable PNET. To our knowledge, this is the first report of the use of multimodality therapy (neoadjuvant chemotherapy ± chemoradiation and surgery) in the treatment of borderline resectable PNET.