Multivariate analysis of metastasis-related risk factors for patients with gastroenteropancreatic neuroendocrine tumors based on clinicopathological and endoscopic features

Abstract

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are relatively uncommon. Unfortunately, epidemiological studies on the incidence of GEP-NETs worldwide have reported a marked increase in the detection of these tumors. Although they often exhibit relatively indolent clinical courses, GEP-NETs have the potential for lethal progression, especially in patients who present with advanced disease. Early detection and surgical removal is currently the only reliable curative treatment for GEP-NET patients. The objective of this study was to analyze the clinicopathological characteristics of GEP-NETs and explore the metastasis-related risk factors of patients with GEP-NETs. One hundred and forty-six patients diagnosed pathologically with GEP-NETs from January 2001 to January 2015 at the Second Xiangya Hospital of Central South University were retrospectively evaluated. We retrieved and analyzed information concerning clinical characteristics and metastasis-related risk factors, and used Chi-square test and logistic regression analysis to analyze the clinicopathological characteristics of GEP-NETs and explore the association between tumor metastasis and possible related risk factors. The results revealed that the most common clinical manifestations were abdominal pain (n=88), alteration in the character of stool (n=58) and melaena (n=33). Rectum (91/146, 62.3%) and stomach (19/146, 13.0%) were the main sites of metastasis. Both Chi-square test and logistic regression analysis showed that tumor size (P<0.05), tumor type (P=0.008) and peritumoral lymphatic vessel density (LVD) (P=0.004) were significantly correlated with tumor metastasis. Neither Chi-square test nor logistic regression analysis indicated that gender (P>0.05), age (P>0.05), tumor location (P>0.05), tumor number (P>0.05), chromaffin granule protein A [chromogranin A (CgA), P>0.05], synaptophysin (Syn, P>0.05) or intratumoral LVD (P>0.05) had a significant correlation with tumor metastasis. Chi-square test revealed that tumor grade was significantly correlated with tumor metastasis. In conclusion, GEP-NETs may occur in multiple sites of the digestive system and lack specific clinical manifestations. Tumor size, tumor type, peritumoral LVD, total LVD and tumor grade are metastasis-related risk factors for GEP-NET patients.