Peptide receptor radionuclide therapy as neoadjuvant therapy for resectable or potentially resectable pancreatic neuroendocrine neoplasms

Background: Peptide receptor radionuclide therapy is a valid therapeutic option for pancreatic neuroendocrine neoplasms. The aim of this study was to describe an initial experience with the use of peptide receptor radionuclide therapy as a neoadjuvant agent for resectable or potentially resectable pancreatic neuroendocrine neoplasms. Methods: The postoperative outcomes of 23 patients with resectable or potentially resectable pancreatic neuroendocrine neoplasms at high risk of recurrence who underwent neoadjuvant peptide receptor radionuclide therapy (peptide receptor radionuclide therapy group) were compared with 23 patients who underwent upfront surgical operation (upfront surgery group). Patients were matched for tumor size, grade, and stage. Median follow-up was 61 months. Results: The size (median greatest width) of the primary pancreatic neuroendocrine neoplasms decreased after neoadjuvant peptide receptor radionuclide therapy (59 to 50 mm; P =.047). There were no differences in intraoperative and postoperative outcomes and there were no operative deaths, but the risk of developing a pancreatic fistula tended to be less in the peptide receptor radionuclide therapy group when compared to the upfront surgery group (0/23 vs 4/23; P <.02). The incidence of nodal metastases at the time of resection was also less in the peptide receptor radionuclide therapy group (n = 9/23 vs 17/23; P <.02). Neither median disease-specific survival (not reached in either group; P =.411) nor progression-free survival (52 vs 37 months; P >.2) differed between groups, but progression-free survival in the 31 patients who had an R0 resection seemed to be greater in the 15 patients in the peptide receptor radionuclide therapy group versus 16 patients the upfront group (median progression-free survival not reached vs 36 months; P <.05). Conclusion: Neoadjuvant peptide receptor radionuclide therapy for resectable or potentially resectable pancreatic neuroendocrine neoplasms in patients with high-risk features of recurrence seems to be beneficial, but well-designed and much larger prospective trials are needed to confirm the safety and the oncologic value of this approach.