Corroborating these correlations, in our cohort of invasive corticotrophinomas, with underexpression of CDKN2A, the mean tumor size was significantly higher (27.7 ± 11.2 mm) than in the non-invasive corticotrophinomas (10.9 ± 4.8 mm), even when we consider only the size of MACs (15.40 ± 4.04 mm). This evidence concerns the gene CDKN2A and neoplasm.