Pure ovarian immature teratoma, a unique and curable disease: 10 years’ experience of 32 prospectively treated patients

Objective: To report and evaluate a conservative and individualized treatment policy in a homogeneously selected series of patients affected by pure ovarian immature teratoma. Methods: This prospective trial, with specific treatment policies according to stage and grade, was planned and started in 1982. The study population consisted of 32 patients affected by pure immature teratoma, with the exclusion of mixed germ cell tumors. Fertility-sparing surgery was performed whenever possible. Surgery alone, with careful follow-up, was adopted for stage I or II according to the International Federation of Gynecology and Obstetrics (FIGO) and grade 1 or 2 tumors. The other patients, with stage III or with grade 3 stage I or II tumors, or those referred at relapse, were treated with platinum-based chemotherapy regimens. Results: Thirty of 32 patients underwent fertility-sparing surgery. Ten of 32 patients received chemotherapy after surgery, either as adjuvant treatment or in the presence of visible tumor. All 32 patients are alive and disease-free, with a median follow-up from surgery of 47 months (range 11-138). In six patients, regardless of the administration of chemotherapy, the tumor either spontaneously differentiated toward mature glia or increased in volume, mimicking progression but still remaining completely mature. Five of six patients wishing to procreate had a total of seven normal pregnancies. Conclusions: Pure ovarian immature teratoma is a potentially curable disease with a unique natural history. Our data substantiate the hypothesis that low-grade and low-stage tumors do not require chemotherapy, and that a fertilitysparing surgical approach is warranted in all cases.