Prognostic factors of small non-functional pancreatic neuroendocrine tumors / 中华消化杂志

ABSTRACT

Objective To investigate the clinical features and prognostic factors of small (maximum diameter≤ 2.0 cm) non-functional pancreatic neuroendocrine tumors (NF-PNET).Methods From January 2002 to April 2017,the clinical data of 18 patients with small NF-PNET were retrospectively analyzed.The prognosis and clinical pathological features were investigated.According to the prognosis,the patients were divided into death group (four cases) and disease-free survival group (14 cases).Fisher's exact test and Mann-Whitney rank inspection were performed for statistical analysis.Results All 18 patients (nine males,nine females) aged 23 to 80 years old,median age 52.5 years old received radical resection.The median follow-up time was 54 months.Four patients died during the follow-up.There was no statistically significant difference in median age (61.0 years,32.0 to 80.0 years vs 49.0 years,23.0 to 72.0 years) and median tumor maximum diameters (1.9 cm,0.8 to 2.0 cm vs 1.5 cm,0.8 to 2.0 cm) between the death group and disease-free survival group (Z=-1.223 and-0.752,P=0.233 and 0.505).Compared with that of disease-free survival group,tumor differentiation degree of the death group was lower (poor/high differentiation,2/2 vs 0/14),and the difference was statistically significant (Fisher's exact test,P=0.039).However,there was no significant difference in histological grades (G1/G2/G3,1/1/2 vs 9/5/0;Fisher's exact test,P=0.057).The distribution of tumor in death group and disease-free survival group was similar.The proportion of patients with tumor at pancreatic head was 2/4 and 6/14 of the death group and disease free survival group,respectively.The surgical methods of the death group included pancreaticoduodenectomy (two cases),distal pancreatectomy (one case),and total pancreatectomy (one case),and there was no statistically significant difference in rates of surgical methods between the two groups (Fisher's exact test,P=0.260).Conclusion Age,tumor maximum diameter,degree of differentiation,histological grade and surgical methods may be correlated with poor prognosis of small NF PNET.