Prognostic factors at diagnosis and value of WHO classification in a mono-institutional series of 180 non-functioning pancreatic endocrine tumours

Background: Non- functioning pancreatic endocrine tumours ( NF- PETs) are an aggressive gastroenteropancreatic neoplasm. The present study assessed survival, value of World Health Organisation ( WHO) classification and prognostic utility of clinicopathological parameters at diagnosis. Patients and methods: From 1990 to 2004, 180 patients with NF- PETs were entered in a prospective database, and predictors of prognosis were tested in uni- and multivariate models. Results: There were 25 ( 14%) benign lesions, 38 ( 21%) neoplasms of uncertain behaviour, 100 well- differentiated carcinomas ( 56%) and 17 poorly differentiated carcinomas ( 9%). Radical resection was possible in 93 cases ( 51.6%). Overall 5-, 10- and 15- year survival rates were 67%, 49.3% and 32.8%, respectively, and were significantly higher in radically resected patients ( 93%, 80.8% and 65.2%, respectively; P < 0.00001). By multivariate analysis, poor differentiation [ hazard ratio ( HR) 7.3; P = 0.0001], nodal metastases ( HR 3.05; P = 0.02), liver metastases ( HR 3.29; P = 0.003), K(i)- 67 > 5% ( HR 2.5; P = 0.012) and weight loss ( HR 3.06; P = 0.001) were significantly associated with mortality. Conclusion: This study confirms the good long- term survival of patients with NF- PETs and the prognostic value of WHO classification, liver metastases, poor differentiation, Ki- 67, nodal metastases and weight loss. These latter two parameters have a prognostic value similar to that of liver metastases and Ki- 67.