Gastroenteropancreatic (GEP) neuroendocrine tumors (NETs) are a heterogeneous group of malignancies.1 They were previously regarded as rare, but in fact are increasing in incidence2 (3.65 per 100,000 individuals per year).3 Based on the 2010 World Health Organization (WHO) classification, NETs can be divided into 3 groups: Grade 1 (Ki-67 ≤2%), Grade 2 (Ki-67 3%–20%), and Grade 3 (G3, Ki-67 > 20%).4 G3 NETs are also called neuroendocrine carcinomas. This evidence concerns the gene MKI67 and neuroendocrine carcinoma.