MKI67 and neuroendocrine carcinoma: Conversely, Elvebakken et al. confirmed that GEP-NEC with Ki-67 ≥ 55% had a significantly better response rate to chemotherapy compared to GEP-NECs with Ki-67 < 55%, but no difference in OS between GEP-NECs <55% and GEP-NECs ≥55% was found [11].