Bilimoria KY et al. (2008) Prognostic score predicting survival after resection of pancreatic neuroendocrine tumors: analysis of 3851 patients. Ann Surg 247: 490–500

Pancreatic neuroendocrine tumors (PNETs) are a rare form of pancreatic neoplasm. The relatively low incidence of this disease has limited the determination of prognostic factors, and a staging system has been lacking. Now, Bilimoria et al. report a postresection prognostic scoring index for PNETs.

By searching the National Cancer Data Base records from 1985 to 2004, the researchers identified 3,851 patients who had undergone resection of PNETs (median follow-up 51 months). On multivariate analysis, older age was significantly associated with an increased risk of death—compared with patients aged <55 years, the hazard ratio for death for patients aged 55–75 years was 1.57 (95% CI 1.28–1.91). Patients with high-grade as opposed to low-grade tumors and those who underwent pancreaticoduodenectomy rather than distal pancreatectomy also had higher risks of death, as did patients with distant metastases (P <0.0001, P = 0.04 and P = 0.004, respectively). A prognostic scoring index was then developed on the basis of the three most powerful prognostic factors—patient age, tumor grade and distant metastasis. Patients with complete information for all three variables were assigned prognostic scores for each factor (0 points = most favorable) and were then divided into three groups on the basis of their scores. The observed overall survival rate at 5 years in patients in prognostic group 1 (total score 0 points) was 76.7%, compared with 50.9% for those in group 2 (1–2 points) and 35.7% for those in group 3 (≥3 points). Cox proportional hazards modeling showed that in comparison with patients in group 1, patients in groups 2 or 3 had significantly greater risks of death (P <0.0001 for both).

The authors conclude that the postresection prognostic score can successfully predict outcome in patients with PNETs.