In the PORTEC‐3 (Adjuvant Chemoradiotherapy Versus Radiotherapy Alone in Women With High‐Risk Endometrial Cancer) trial, all but one HER2‐positive cases were p53abn EC, including a diversity of histologic subtypes (serous, n = 9, 37.5%; endometrioid, n = 6, 25.0%; clear cell, n = 5, 20.8%).9 This evidence concerns the gene ERBB2 and endometrial cancer.