Clinical outcome of lymphadenectomy in malignant ovarian germ cell tumors: a systematic review and meta-analysis

Malignant ovarian germ cell tumors (MOGCTs) are predominately diagnosed in young patients and account for most preadolescent malignant ovarian tumors. Currently, due to the high sensitivity of MOGCTs to chemotherapy and the optimal survival rate after chemotherapy, some researchers have recommended opting for non-surgical treatment. However, the effect of lymphadenectomy (LND) on the survival of patients with MOGCT remains controversial. We conducted a systematic review and meta-analysis to compare the clinical outcomes of LND and non-LND in MOGCT surgeries in order to summarize the clinical experience. PubMed, Embase, Web of Science, Cochrane Central Register of Controlled Trials (CENTRAL), International Clinical Trials Registry Platform (ICTRP), and Clinical Trials.gov were searched from inception to December 26, 2021. Data on the rates of survival, relapse, and adverse effects were evaluated using Review Manager software. Fourteen studies with 10,759 participants were included in this review. There were 5863 and 4896 patients in the LND- and LND+ groups, respectively. Pooled results showed that although disease-free survival (DFS) was significantly improved in the LND+ group compared to the LND- group (HR: 0.74; 95% CI: 0.56 to 0.97; 2091 participants), LND did not significantly affect overall survival (OS) (HR: 0.82; 95% CI: 0.51 to 1.31; 5298 participants). The operation time was significantly longer in the LND+ group than in the LND- group (P < 0.001). Blood loss (P=0.004) and complication rate (P=0.003) were also significantly higher in the LND+ group than in the LND- group. There was no significant difference in mortality rate (P=0.500). LND was associated with an improvement in DFS. However, there was no significant difference in OS in MOGCTs. We recommend that LND should not be a routine surgery for children or young patients with MOGCTs; although it may be beneficial for older people, advanced stage tumors, specific pathological types, and non-chemotherapy patients.