Primary squamous cell carcinoma of the ovary. Review of the literature.

Purpose: Primary squamous cell carcinoma (SCC) of the ovary is rare. Most cases arise from a cystic teratoma or less frequently from Brenner tumor or endometriosis. We reviewed 36 cases of primary ovarian SCC reported in the literature including a case diagnosed and treated in our institution.
Methods: Data was collected by using the key-words "primary squamous cell carcinoma" and "ovary" on Google Scholar and PubMed in April 2018. All reviewed cases were analyzed according to diagnosis, surgical approach, adjuvant therapy and outcome.
Results: To date 23 articles presenting 36 cases of primary ovarian SCC are reported. Nine patients had stage I, 8 stage II, 11 stage III and 5 stage IV disease, whereas 3 patients had in situ carcinoma. All patients underwent surgery (mainly hysterectomy with bilateral salpingo-oophorectomy). Adjuvant therapy was reported in 24 patients, 15 of which received chemotherapy, 6 radiotherapy and 3 a combination of both. Chemotherapy regimens were similar to the ones used in ovarian carcinoma (more often platinum plus paclitaxel). Follow-up period was in general short and survival varied between 9 days and 14 years, depending on the stage at diagnosis.
Conclusions: Primary ovarian SCC is a rare entity with poor prognosis, compared to serous carcinoma. Treatment is usually extrapolated from classical ovarian carcinoma algorithms, including surgical management combined with adjuvant chemotherapy with or without radiotherapy. Further investigations are needed to define optimal treatment, such as chemotherapy regimens and the role of radiotherapy and lymph node dissection.