MKI67 and neuroendocrine carcinoma: In contrast, patients with a poorly differentiated NEC, but Ki67 expression of >60%, respond to cisplatin-based chemotherapy.16, 17, 18 In addition, PD-NEC may also include a combined component of a conventional carcinoma (MANEC),19 such as a squamous cell carcinoma or adenocarcinoma, but they do not typically contain a lower-grade WD-NEN.20, 21 Therefore, the availability of biomarkers that could better characterize G3 GEP NENs could have crucial therapeutic implications, indicating the most efficient pharmacological strategy.