Cervical mixed small cell neuroendocrine carcinoma and adenocarcinoma with genital tract dissemination: a case report and literature review.

BACKGROUND: Primary mixed neuroendocrine-non-neuroendocrine neoplasms (MiNENs) of the cervix are exceedingly rare. This report describes a case of human papillomavirus (HPV)-associated cervical MiNEN composed of adenocarcinoma and small cell neuroendocrine carcinoma (SCNEC) of cervix. Clinical and pathological findings suggest that the adenocarcinoma component extended to the endometrium, bilateral fallopian tubes, and ovaries via genital tract dissemination. CASE PRESENTATION: A 48-year-old female presented with abnormal vaginal discharge for more than eight months and HPV genotyping test was positive for type 18. Pelvic MRI revealed cervical space-occupying lesions and cystic changes in the adnexal region. Gross examination revealed an ulcerative cervical mass, thickened and dilated fallopian tubes, and polycystic ovaries. The tumor was solid, and the cut surface was grayish white with mucus. Histologically, the cervical tumor comprised 65% SCNEC and 35% HPV-associated adenocarcinoma, both of which diffusely expressed p16. Adenocarcinoma was identified in the endometrium and bilateral fallopian tubes and ovaries, and its morphology, immunophenotype, and HPV infection status were consistent with those of cervical adenocarcinoma, suggesting that the cervical adenocarcinoma disseminated along the reproductive tract. Despite receiving systemic chemotherapy and local radiotherapy following surgery, the patient unfortunately passed away due to the progression of the disease in November 2022. CONCLUSIONS: Cervical MiNENs are highly aggressive malignancies associated with poor prognoses. HPV-associated tumors may spread contiguously through the reproductive tract, mimicking primary tumors of the endometrium, fallopian tubes, or ovaries. Accurate diagnosis and effective management of patients rely on meticulous postoperative histopathological evaluation.