50-year appraisal of gastrinoma: recommendations for staging and treatment.
BACKGROUND: Gastrinoma is a rare neuroendocrine tumor associated with ulcerogenic syndrome. The purpose of this study was to provide information on current controversies related to treatment, including staging, patient selection, and outcomes for surgical resection. STUDY DESIGN: A retrospective review of 106 patients with gastrinoma. Patients were classified as sporadic gastrinoma (SG) or MEN. End points of analysis included disease-free and disease-specific survival. Kaplan-Meier survival analysis was performed and significance (p < 0.05) was determined by Mantel-Haenszel log-rank test. RESULTS: Gastrinoma can be staged by TNM criteria into four groups (stage 0, I, II, and III), which had notably different survival curves, dependent on tumor size and distant metastases (p < 0.0001), but independent of lymph node metastases (p = 0.324). Surgical resection was possible in 72 patients (SG, n = 50; MEN, n = 22). Durable cure rate for SG was 26%, compared with 4% for MEN-1. Surgical resection achieving gross removal of all tumor resulted in improved survival in both SG and MEN patients (p < 0.0001). Improved survival was independent of a normal postoperative serum gastrin. Stage III was highly predictive of incomplete resection and the associated failure to improve survival (p = 0.0001). CONCLUSIONS: Staging provides a reliable method for the clinician to select patients for operation and to provide a prognosis, and should permit better comparisons of treatment between institutions. In the management of gastrinoma, it is recommended that SG and MEN patients with clinical stage I and II disease have surgical exploration, patients with stage III disease not have mandatory surgical treatment, and some stage 0 patients might not need routine surgical exploration.