MKI67 and neuroendocrine carcinoma: Key determinants include the degree of differentiation—classified as well-differentiated (NETs) or poorly differentiated (neuroendocrine carcinomas, NECs)—as well as grading parameters such as the mitotic index and Ki67 proliferative index, TNM staging, immunohistochemical expression of somatostatin receptors, and additional histological and molecular markers including DAXX/ATRX genes expression.