Clinicopathological and prognostic significance of immunophenotypic characterization of endocervical adenocarcinoma using CLDN18, CDH17, and PAX8 in association with HPV status

In 2020, the WHO published a new system for classifying invasive endocervical adenocarcinoma based on histological features and high-risk human papillomavirus (HPV) infection. However, immunophenotypes of each histological subtype require further investigation. We immunohistochemically analyzed 66 invasive endocervical adenocarcinomas using three cell-lineage–specific markers: claudin 18 (CLDN18) for gastric, cadherin 17 (CDH17) for intestinal, and PAX8 for Mullerian epithelial cells. We identified five immunophenotypes of endocervical adenocarcinoma: gastric (21%); intestinal (14%); gastrointestinal (11%); Mullerian (35%); and not otherwise specified (NOS) (20%). Adenocarcinomas with gastric immunophenotype, characterized by aging (p = 0.0050), infrequent HPV infection (p