In hyperplasia, MLH1 hypermethylation was similarly observed (11/27 [41%]), but the PTEN mutation was less frequent (5/27 [19%]), observed only in atypical hyperplasias; among the 5 patients with a PTEN mutation, the 2 patients with frameshift mutations had MLH1 hypermethylation, but the 3 patients with missense mutations had unmethylated MLH1.
C0020507
Hyperplasia