Human papillomavirus DNA in adenocarcinoma in situ, microinvasive adenocarcinoma of the uterine cervix, and coexisting cervical squamous intraepithelial neoplasia.

Previously, human papillomavirus (HPV) DNA, mainly HPV-18 DNA, was detected in more than 40% (17/40 cases) of invasive adenocarcinoma of the uterine cervix in our laboratory. In order to identify HPV DNA in the precursor lesions of adenocarcinoma of the cervix, 11 cases of adenocarcinoma in situ containing microinvasive adenocarcinoma and 10 cases of adenocarcinoma in situ were studied for the presence of HPV DNA by in situ hybridization using highly sensitive 3H-labeled HPV-16 and HPV-18 DNA probes. HPV types present in cervical squamous intraepithelial neoplasia (CIN) coexisting with adenocarcinoma in situ and microinvasive adenocarcinoma were also studied. Apart from the coexisting CIN II-III with glandular neoplasms, 48 cases of CIN III (severe dysplasia and squamous carcinoma in situ) removed by conization or hysterectomy and known to be free of adenocarcinoma were used for comparison. HPV DNA was detected in 64% of microinvasive adenocarcinoma, 70% of adenocarcinoma in situ, and 63% of the control CIN III. HPV-18 DNA was the preponderant type of HPV DNA found in adenocarcinoma in situ and microinvasive adenocarcinoma. All cases of HPV DNA-positive microinvasive adenocarcinoma contained the same type of HPV DNA as the lesions of coexisting adenocarcinoma in situ. CIN coexisting with microinvasive adenocarcinoma or adenocarcinoma in situ contained the same type of HPV as identified in the glandular lesions, whereas all of the HPV DNA-positive control CIN III cases contained HPV-16 DNA. These results suggest that adenocarcinoma in situ is a precursor lesion of adenocarcinoma of the cervix that contains HPV DNA, and that CIN coexisting with adenocarcinoma may be a result of a metaplastic process of adenocarcinoma or of bidirectional differentiation of the affected reserve cells.