HPV-Independent Cervical Adenocarcinoma Discovered by Cytology-Based Screening: A case report of gastric type adenocarcinoma of the uterine cervix from cytopathology to histopathology

Abstract Introduction/Objective In recent years, the relative prevalence of adenocarcinoma has increased, comprising 20–25% of all cervical carcinomas in developed countries. Approximately 15% of cervical adenocarcinomas are unrelated to human papilloma virus (HPV) infection. With the shift toward HPV primary testing, an increased understanding of HPV-independent cervical adenocarcinomas becomes more important. Methods/Case Report This case report demonstrates a rare case of gastric-type adenocarcinoma (GAS) of the cervix discovered during a routine well-woman exam. Patient-reported episodes of vaginal spotting were noted prior to screening. HPV testing by PCR on the initial pap smear was negative. Cytology findings raised concerns about endocervical glandular cell abnormalities. Subsequent cervical biopsy revealed GAS, a finding supported by positive CK7, MUC5AC, CDX2, and aberrant (mutant) p53 expression by immunohistochemistry. HPV independence was further confirmed by negative results on mRNA ISH for high-risk HPV and HPV16/18. Results (if a Case Study enter NA) NA Conclusion Here we discuss the impact of cytology-based screening on HPV-independent cervical cancers, with focus on adenocarcinoma. While the move to primary HPV screening has been shown to be effective at identifying HPV-related neoplasms, it ineffectively addresses HPV-independent malignancies. In this particular population, cytology-based screening remains indispensable. The described case demonstrated subtle cytologic features consistent with endocervical glandular abnormality, ultimately correlating with subsequent histologic findings of HPV-independent GAS. Negative HPV results combined with subtle cytomorphologic changes displayed by some adenocarcinomas on PAP smear could present a significant diagnostic pitfall. Additionally, p16+ expression attributable to aberrant p53 pathways (rather than HPV) may further contribute to potential diagnostic errors. While further research into best practices for early detection of HPV-independent cervical neoplasias should be conducted, this team suggests both clinical survey and referral for cytologic screening following reports of abnormal vaginal bleeding and/or watery discharge and screener education focused on cervical GAS.