Superficially invasive cervical squamous cell carcinoma metastatic to ovarian endometriotic cyst wall, a case report and brief review of the literature

Background: Although cases of cervical squamous cell carcinoma metastatic to the ovary have been previously documented, we report the first case of superficially invasive squamous cell carcinoma metastatic to the ovary. Case presentation: A 45-year-old woman with a two-year history of ovarian endometriosis confirmed by ultrasound underwent oophorectomy. On microscopic examination, a focus of malignant stratified epithelium, initially interpreted as transitional cell carcinoma, was identified within the endometriotic cyst wall. Examination of the hysterectomy specimen revealed superficially invasive squamous carcinoma of the cervix. In addition, two triploid, CD45-negative cells were detected during the analysis of the peripheral blood for circulating tumor cells (CTC). High-risk HPV was detected on the sections of endometriosis containing cancerous area by using hybrid capture 2 assay, supporting the diagnosis of metastatic squamous cell carcinoma originating from the uterine cervix. Conclusion: This is the first report of superficially invasive squamous cell carcinoma metastatic to the ovary. Such finding could be misdiagnosed as primary ovarian transitional cell carcinoma, squamous cell carcinoma originating from metaplastic epithelium within endometriosis, or squamous cell carcinoma arising in a teratoma.