The median Ki-67 index of all patients was 60% (range: 18–97%) but differed significantly (Wilcoxon test: p < 0.001) between NET G3 (27%, range: 18–60%) and NEC (80%, range: 22–97%), with apparent differences between primary tumor sites, see Fig. 1. Here, MKI67 is linked to neuroendocrine carcinoma.