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.