Demographic, clinical, histological features in patients with gastrointestinal neuroendocrine tumors and the relationship of these features with survival

Aim: GI-NET is a group of neoplasia consisting of amine and acid producing cells with different hormonal profiles. Although the entire GIS accounts for about 2% of tumors, recent research reveals that the incidence rate has increased. Given the increasing incidence in GI-NETs, more and more extensive research is needed on this subject. In this regard, the demographic and clinicopathological features of the patients diagnosed with GI-NET and their relationship with survival were investigated in this study. Methods: Patients diagnosed with GI-NET between 01.01.2009-31.12.2019 at İnönü University, Medical Faculty, the Department of Gastroenterology were included in this study. The data in 34 patient files were analyzed retrospectively. Gender, age, tumor location, metastasis status, tumor number, tumor diameter, tumor grade, Ki-67 index, the presence of necrosis, ulcer and bleeding, the presence of adenocarcinoma coexistence, lymphovascular invasion and perineural invasion, the presence of curative operation, and the relationships of these factors with overall survival were examined. Results: 61.8% of the patients included in the study were male and 38.2% were female. The average age of the patients was 60.74. The most common tumor location was in the stomach (26.5%) and liver (26.5%). Apart from this, 17.6% of NETs were seen in the pancreas, 11.8% in the colon, 8.8% in the rectum, 5.9% in the small intestine and 2.9% in the appendix. There was no statistically significant difference between tumor location by gender and age . The tumor diameter ranged from 0.2 cm to 13.91 cm in all cases, but the average tumor diameter was 3.84 cm. Solitary tumor was found in 51.5% of cases and multiple tumors in 48.5% of cases. The most common grade was Grade 1 with 41.2% of occurence. The average of Ki-67 index of 22 cases whose Ki-67 index was specified in pathology reports was 18.36%. Necrosis was found in 33.3% of the patients, ulceration in 27.3% and bleeding in 27.3%. Adenocarcinoma coexistence was found in 24.2% of the patients, lymphovascular invasion in 36.4% and perineural invasion in 27.3%. There was metastasis in 52.9% of cases. The rate of medical treatment was 48.5%. The median overall survival time of the patients was 23.1 months. In addition, 1-year survival was 74.9%, 2-year survival was 44.6%, and 5-year survival was 35.7%. A statistically significant difference was found between tumor grade and the presence of metastasis, and the survival of 1, 2 and 5 years (p = 0.003 and p = 0.005). Conclusion: The tumor grade and the presence of metastasis in gastrointestinal neuroendocrine tumors were found to be the most important prognostic factors affecting overall survival. Keywords: Gastrointestinal Neuroendocrine Tumor (GI-NET), Overall Survival