MKI67 and digestive system mixed adenoneuroendocrine carcinoma: Subsequently, NETs were categorized into five types, namely NET Grade 1, NET Grade 2, NEC (large cell or small cell), mixed adeno-neuroendocrine carcinoma (MANEC), and hyperplastic and neoplastic lesions, in the 2010 WHO classification according to the grading by the Ki-67 labeling index [8].