Clinicopathological Characteristics and Prognosis-Related Factors of Resectable Pancreatic Neuroendocrine Tumors A Retrospective Study of 104 Cases in a Single Chinese Center

Objective The purpose was to describe the clinicopathological characteristics of pancreatic neuroendocrine tumors (pNETs) and evaluate prognosis-related factors in potentially resectable pNETs. Methods The clinical data of 104 patients with pNETs who underwent surgery were retrospectively analyzed. Results The mean (SD) age was 49.8 (14.6) years. The percentages of TNM stages I, II, III, and IV tumors were 25.0%, 44.2%, 22.1%, and 8.7%, respectively. Twenty-seven cases were functional. Nonfunctional pNETs were more common in patients with large tumors, advanced age, higher mitotic count, neural invasion, extrapancreatic organ invasion, liver metastases, and advanced staging (P < 0.05). The 5-year overall survival rate was 93%. The relapse rate was 28.6% (28/98), and the mean (SD) relapse time was 38.7 (31.7) months. Reduced survival rate was associated with older patients (>60 years) (P = 0.026), patients with a higher Ki-67 index (>2%) (P = 0.024), regional lymph node metastases (P = 0.033), liver metastases (P = 0.015), neural invasion (P = 0.017), necrosis (P = 0.042), and major vascular invasion (P = 0.023). Age of more than 60 years (P = 0.047; hazard ratio [HR], 5.2), major vascular invasion (P = 0.030; HR, 5.8), and a Ki-67 index greater than 2% (P = 0.008; HR, 10.3) were independent predictors. Conclusions Nonfunctional pNETs were more common with aggressive clinical presentation. Age of more than 60 years, major vascular invasion, and a Ki-67 index greater than 2% were independent predictive factors. Patients who underwent a potentially curative resection seemed to achieve long-term survival.