Objective To evaluate the role of omentectomy and lymphadenectomy in the treatment of clinically apparent early-stage malignant ovarian germ cell tumors.

Methods We retrospectively reviewed 245 patients with malignant ovarian germ cell tumors (yolk sac tumor, dysgerminoma, and immature teratoma) and with clinically early-stage disease, who were treated at Sun Yat-sen University Cancer Center between January 1, 1970 and December 31, 2017. The survival of patients who underwent either omentectomy or lymphadenectomy, or both (omentectomy/lymphadenectomy group) was compared with that of patients who did not undergo omentectomy or lymphadenectomy (non-omentectomy/lymphadenectomy group).

Results Sixty patients were diagnosed with yolk sac tumor, 74 with dysgerminoma, and 111 with immature teratoma. Of these 245 patients, 216 patients had stage I disease, 28 patients had stage II, and 1 patient had stage IIIA. There were 190 patients who underwent omentectomy and/or lymphadenectomy and 55 patients in the non-omentectomy/lymphadenectomy group, respectively. In the omentectomy/lymphadenectomy group, 112 patients underwent both omentectomy and lymphadenectomy, 71 underwent omentectomy only, and 7 underwent lymphadenectomy only. Two hundred and fourteen of 245 patients (87.3%) received post-operative chemotherapy. Median follow-up was 73 months (range 1–388). The 10-year overall survival rates in the omentectomy/lymphadenectomy group and non-omentectomy/lymphadenectomy groups were 96.8% and 100%, respectively (p=0.340). Multivariate analysis evaluating all potential prognostic factors showed that omentectomy and lymphadenectomy are not prognostic factors for survival.

Conclusions Omentectomy and lymphadenectomy do not appear to improve survival and may be omitted in patients with clinically apparent early-stage malignant ovarian germ cell tumors.