Detection And Clinical Implication Of Pathological Diagnosis And Serum Examination In Gastric Primary Neuroendocrine Neoplasm

Objective:To analyze retrospectively and summarize clinical manifestations, pathological features and immunohistochemical features of primary gastric (including oesophagogastric junction) NEN (Neuroendocrine neoplasm). To evaluate the relationship among serum chromogranin A (CgA) expression, diagnosis, treatment and prognosis judgment.Methods:75primary gastric NEN data were analyzed retrospectively, CgA and Syn expression of tumor tissues and metastatic lymph nodes were detected. Serum samples of pre-operation and post-operation and post-operative tumor tissue samples of78patients, who were diagnosed as gastric adenocarcinoma, were collected and the expressions of CgA and Syn were detected by means of ELISA technique. The relationship of CgA and Syn levels between tumor tissues and serum was compared.Result:(1) G1, G2, G3and MANEC of75primary gastric NEN was16.00%(12/75),1.33%(1/75),53.33%(40/75) and29.33%(22/75) respectively. The immunohistochemical expression of CgA, Syn and Ki-67labelling index in tumor tissues were of important significance in the diagnosis and classification of tumors. Immunohistochemical detection in lymph node metastasis was useful in the treatment and prognosis of MANEC. MANEC can be observed as sporadic neuroendocrine cells in adenocarcinoma, but lymph node metastasis with simple NEC was normal in some cases.(2) In78cases diagnosed as gastric adenocarcinoma, the immunohistochemical positive expression of CgA was detected in20cases (25.64%) in varying proportions (10%-60%). Pre-operation expression of CgA in serum and immunohistochemical expression of CgA in tumor tissues were positively correlated and statistically significant (P=0.012), the correlation index was0.283. The relative difference of serum CgA level and immunohistochemical expression of CgA in tumor tissues were negatively correlated and statistically significant (P=0.002), the correlation index was-0.345. ROC curve indicated that when49.05mg/ml was chosen as cut off value of pre-operation serum CgA, the sensitivity and the specificity of predicting immunohistochemical positive expression of CgA in tumor tissues were80.00%and41.40%respectively. When-5.50%was chosen as cut off value of serum CgA level relative difference, the sensitivity and the specificity of predicting immunohistochemical positive expression of CgA in tumor tissues were60.00%and91.40%respectively. Conclusion:Gastric NEN was considered as benign、low-grade and high-grade large span biological behavior, obvious morphological difference, diagnosis difficulty in pre-operation biopsy, low coincidence rate of pre-operation biopsy and post-operation pathological diagnosis. Immunohistochemical detection of CgA, Syn and CD56was useful in improving detection rate of NEN. Immunohistochemical detection of primary tumors and metastatic lymph nodes was significant in improving diagnosis accuracy rate and judging prognosis. Recording baseline value of pre-operation serum CgA and dynamic monitoring of post-operation serum CgA is important for the screening, diagnosis, therapeutic effect evaluation and relapse monitor, which should be served as one of routine examination in gastrointestinal tumor patients.