Counterpoint: Integration of Molecular Subtype and Histotype/Grade Into One Classification System for Endometrial Carcinoma

Abstract The establishment of 4 endometrial carcinoma molecular subtypes by The Cancer Genome Atlas project and their surrogates (POLE mutated, mismatch repair–deficient, p53 abnormal, and no specific molecular profile) invigorated a debate on how to integrate these within the traditional histotype/grade classification. Specific issues of contradicting histotype/grade and molecular subtype diagnoses will be discussed with illustrated examples. The hierarchy of histotype/grade and molecular subtype is interdependent. Pathologists should aim to integrate histotypes/grades and molecular subtypes to provide one consistent and clinically relevant diagnosis.