Neoadjuvant treatment of nonfunctioning pancreatic neuroendocrine tumors with [¹⁷⁷Lu-DOTA⁰,Tyr³]octreotate

Pancreatic neuroendocrine tumors (NETs) are rare neoplasms for which surgery has almost the only potential for cure. When surgery is not possible because of tumor size and vascular involvement, neoadjuvant treatment with [¹⁷⁷Lu-DOTA⁰,Tyr³]octreotate (¹⁷⁷Luoctreotate) may be an option. Methods: We studied 29 Dutch patients with a pathology-proven nonfunctioning pancreatic NET treated with ¹⁷⁷Lu-octreotate. All patients had a borderline or unre-sectable pancreatic tumor (group 1) or oligometastatic disease (defined as #3 liver metastases) (group 2). Progression-free survival (PFS) was analyzed using the Kaplan-Meier method and Cox proportional hazards modeling. Results: After the treatment with ¹⁷⁷Luoctreotate, successful surgery was performed in 9 of 29 patients (31%). Six patients had a Whipple procedure, 2 patients had a pylorus-preserving pancreaticoduodenectomy, and 1 patient had a distal pancreatectomy and splenectomy. The median PFS was 69 mo for patients with successful surgery and 49 mo for the other patients. For comparison, the median PFS in 90 other patients with a nonfunctioning pancreatic NET with more than 3 liver metastases or other metastases was 25 mo. Conclusion: Neoadjuvant treatment with ¹⁷⁷Lu-octreotate is a valuable option for patients with initially unresectable pancreatic NETs.