OBJECTIVETo study the clinicopathologic and prognostic features of neuroendocrine neoplasm of digestive system with different grades.

METHODSThe clinicopathologic features of 139 cases of neuroendocrine neoplasm occurring in digestive system were retrospectively reviewed and graded according to the 2010 World Health Organization classification of tumours of the digestive system. Immunohistochemical study for synaptophysin, chromogranin A and Ki-67 was carried out. The follow-up and survival data were analysed using Kaplan-Meier method. Prognostic factors were tested by Log-rank testing and independent risk factors were analysed using Cox regression model.

RESULTSAmongst the 139 cases studied, there were 88 cases (63.3%) of grade 1 tumors, 9 cases (6.5%) of grade 2 tumors and 42 cases (30.2%) of grade 3 tumors. There was diffusely positive staining for synaptophysin and chromogranin A in most of the grade 1 and grade 2 tumors. The staining in grade 3 tumors however was focal (P < 0.05). The differences in tumor size, depth of invasion, presence of tumor emboli, perineural permeation, nodal involvement, distant metastasis and survival rate amongst the three groups was statistically significant (P < 0.05).

CONCLUSIONSThere is significant difference in the clinicopathologic and prognostic features of neuroendocrine neoplasm of digestive system with different grades. It is considered as an independent prognostic factor and represents a useful tool for prognostic evaluation of such tumors, both in clinical practice and research.