Retrospective Analysis of Pure Ovarian Immature Teratoma in Patients Aged 15-39 Years: A Turkish Multicenter Study.

To evaluate the clinicopathological characteristics and surgical outcomes in patients with pure ovarian immature teratomas (POITs). In this multicenter study, a retrospective review was made of the databases of six Gynecology Oncology Departments in Turkey to identify patients with POITs who had undergone surgery between 1993 and 2019. Evaluation was made of 48 patients with a median age at diagnosis of 22.5 years (range, 15-37 years). In 40 (83%) patients, stage I was determined and in eight patients, an advanced stage (IIIB, IIIC, and IVB) was determined. Tumors were found to be grade I in 17 (35.4%) cases, grade II in 12 (25%), and grade III in 19 (39.6%). Fertility-sparing surgery was applied to 42 (87.5%) patients and radical surgery to 6 (12.5%). The median follow-up was 60 months (range, 3-246 months). Recurrence was seen in seven patients, all with grade III tumors. In the final pathological examination of recurrent tumors, mature teratoma was reported in five patients, and immature teratoma in one patient. Salvage surgery was not performed in one patient as the tumor was unresectable and so a regimen of bleomycin, etoposide, and cisplatin (BEP) was administered. POITs are rare tumors seen at a young age, and benign or malignant relapse can be seen in these tumors. In this cohort, the malignant recurrence rate was 4.1%, and the benign recurrence rate was 10.4%. All the recurrences were in grade III tumors. Benign recurrences can be treated with surgery alone and the malignant group should be treated with surgery followed by chemotherapy.