MKI67 and laryngotracheoesophageal cleft: Four studies reported on morphology of the different subgroups of patients [9,20,21,22] (n  = 37): among 12 GEP-NECs with a Ki67 LI <55%, 8 were LC carcinomas (66.7%) while 4 had a SC morphology (33.3%); instead, in the subgroup with a Ki67 LI ≥55%, there were 6/14 GEP-NECs with a LC morphology (42.8%) and 8/14 cases with a SC morphology (57.14%).