Clinicopathological study of 100 cases of neuroendocrine neoplasms of the gastroenteropancreatic system: A tertiary cancer center experience

Background: The incidence of gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) is on the rise. Although the clinicopathologic characteristics of NENs have been previously reviewed in the literature, the data published in the Indian literature so far are sparse. This study aims to review the clinicopathological features of GEP-NENs, diagnosed at our institution, and that were classified and graded according to the World Health Organization 2010 classification system. Materials and Methods: One hundred patients with GEP-NENs presenting to our institute from August 2012 to May 2016 were analyzed retrospectively. Demographic data and tumor characteristics were expressed as number, percentage, and mean value. Tumor grade was correlated to metastasis through the Chi-square test. P < 0.05 was considered statistically significant. Results: Of the 100 cases studied, 58 were male and 42 were female. The most common primary site was the pancreas (n = 36), followed by the small intestine (n = 19), esophagus (n = 17), stomach (n = 15), colon (n = 6), rectum (n = 4), and appendix (n = 3). The incidence of neuroendocrine tumor (NET) Grade 1 (NET G1) was higher (n = 40) compared to NET Grade 2 (NET G2) (n = 25) and neuroendocrine carcinoma Grade 3 (NEC G3) (n = 35). Overall in these 100 cases, NET G1 tumors and NET G2 tumors were most common in the pancreas (n = 18/36) and (n = 13/36), respectively. NEC G3 tumors were most common in the esophagus (n = 16/17). The most common site of distant metastasis was the liver (n = 23/26). Conclusion: We elucidated the epidemiological and clinicopathological features of patients presenting to our institute with GEP-NENs.