Clinicopathological analysis of 21 cases of "Synchronous" endocervical and ovarian adenocarcinomas

To comprehensively investigate the clinicopathological characteristics, immunohistochemical (IHC) profiles and HPV status of "synchronous" endocervical and ovarian adenocarcinoma. Retrospective analysis of 21 cases of "synchronous" endocervical and ovarian adenocarcinoma was conducted. HE staining was used for morphological observation. IHC staining was performed to detect expression of p16, Mucin 6, Claudin18.2, NapsinA, and P504S. Testing for human papillomavirus (HPV) infection was carried out using the RNAscope method. Among the 21 cervical cancer cases, eight exhibited pseudostratified nuclear arrangement with prominent apical mitotic figures and apoptotic bodies, 11 had cells with clear cytoplasm and distinct cell borders, while the remaining two displayed hobnail cells. The ovarian tumors recapitulated the morphological spectrum of primary ovarian epithelial tumors and demonstrated invasive growth patterns. Endometrial/myometrial and fallopian tube involvement was observed in some cases, while others presented with lymphovascular space invasion and lymph node metastasis. IHC analysis revealed that all eight cases of both cervical and ovarian adenocarcinoma exhibited diffuse and strong positivity for p16, 11 cases co-expressed Claudin18.2 and Mucin 6, and two cases were positive for both NapsinA and P504S. RNAscope testing results were positive for all eight endocervical and ovarian adenocarcinoma cases. The final classification of eight cases was ovarian metastasis of HPV-associated (HPVA) endocervical adenocarcinoma (EAC) and the remaining 13 as metastasis of HPV independent (HPVI) EAC. The diagnosis of ovarian metastasis from EAC requires careful integration of morphological features with other clinicopathological characteristics. The markers p16, Claudin18.2 and Mucin 6 are useful for diagnosis, with HPV RNAscope testing recommended when necessary. Ovarian metastasis may involve intraepithelial spread along the endometrium/fallopian tube, traditional lymphovascular invasion, and invasive growth patterns.