Is adjuvant chemotherapy indicated in stage I pure immature ovarian teratoma (IT)? A multicentre Italian trial in ovarian cancer (MITO-9)

Objective.Conservative surgery followed by platinum-based chemotherapy is considered the standard approach for stage I immature ovarian teratoma (IT), except for stage IA G1. Nevertheless the use of chemotherapy in stage IA G2–3 and IB–IC is controversial. The aim of this study was to evaluate the outcome of patients with IT in order to define the role of chemotherapy in stage I disease.Methods.Twenty-eight patients with stage I IT treated in MITO centers were retrospectively reviewed. Grade, stage, age, surgical and postoperative treatment were analyzed using χ2 test and T test looking for association with recurrence.Results.Median age was 25.5. Twenty-four patients underwent fertility-sparing surgery. FIGO stages were 19 IA, 2 IB, and 7 IC. Nine patients had grade 1 tumor, 12 grade 2, and 7 grade 3. Nine patients received adjuvant chemotherapy. Overall recurrence rate was 21.4% (2 in chemotherapy group and 4 in the group without treatment). No patients with G1 had recurrence, whereas 25% of G2 and 42.9% of G3 relapsed. Recurrence rate was not significantly different according to stage, grade or adjuvant chemotherapy, whereas it was greater in the group not operated in a MITO center, not staged and of age lower than 20 years, with statistical significance. At recurrence 4 patients presenting with mature teratoma were treated with surgery alone, whereas 2 recurring with IT were treated with surgery plus chemotherapy. After a median follow-up of 59 months all patients are NED.Conclusions.Our study suggests that chemotherapy may be withheld for primary therapy and utilized only for recurrence.