HPV prevalence and genotypes in different histological subtypes of cervical adenocarcinoma, a worldwide analysis of 760 cases

Abstract

The goal of our study was to provide comprehensive data on the worldwide human papillomavirus (HPV) genotype distribution in patients with invasive cervical adenocarcinoma in correlation with histologic tumor subtypes, geographical location, patients' age, and duration of sample storage. Paraffin-embedded samples of 760 cervical adenocarcinoma cases were collected worldwide. A three-level pathology review of cases was performed to obtain consensus histologic diagnoses and 682 cases were determined to be eligible for further analysis. HPV DNA detection and genotyping was performed using SPF-10/DEIA/LiPA(25) system (version 1). Classic cervical adenocarcinoma accounted for 83.1% of cases, while rare histological variants accounted for a few percent of cases individually. HPV positivity varied significantly between the different histologic tumor subtypes. Classic cervical adenocarcinoma showed high HPV positivity (71.8%), while other adenocarcinoma types had significantly lower HPV prevalence (endometrioid 27.3%, serous 25%, clear cell 20%, not otherwise specified 13.9%, and minimal deviation 8.3%). In all, 91.8% of HPV-positive tumors showed the presence of a single viral type and in 7% of cases multiple viral types were detected. Three HPV genotypes, HPV 16, 18, and 45, dominated in all adenocarcinomas and together accounted for 94.1% of HPV-positive tumors. HPV16 was the most common and found in 50.9% of HPV-positive cases, followed by HPV18 (31.6%) and HPV45 (11.6%). HPV prevalence varied depending on geographical region, patient age, and sample storage time. Tumors from older patients and tumor samples with longer storage time showed lower HPV prevalence. Our results indicate that HPV vaccines may prevent up to 82.5% (HPV16/18) and up to 95.3% (9-valent vaccine) of HPV-positive cervical adenocarcinomas, mostly the classic type. HPV testing and vaccination will not provide full coverage for a very small subset of classical adenocarcinomas and most of the rare tumor variants such as clear cell, serous, endometrioid, and minimal deviation.