Results
A total of 651 studies were initially retrieved from database search. Fifteen results were duplicates. Through 3 phases of screening, 614 studies were excluded (466 irrelevant studies, 79 review articles, 61 conference abstracts, 6 ineligible study designs, and a single case study). Eventually, 22 comparative studies (6,825 patients) met our inclusion criteria and were eligible for pooled analysis. Flowchart of selection process is demonstrated in figure 1.
Study design and selection criteria of included studies are summarized in Table S1. Of all studies, 19 were retrospectively conducted (9, 14-31) and three were randomized clinical trials (RCTs) (10, 32, 33). All studies were published between 1995 and 2019 and included patient data collected between 1985 and 2019. Sixteen studies investigated women with advanced disease; 7 studies included patients with FIGO stage III and IV (9, 18, 20, 22, 24, 26, 27), 4 studies included FIGO stage IIIC to IV (14-16, 28), 2 study included stages IIIB to IV (19, 33), 2 included stage IIB to IV (10, 25), and 1 study included stage IIIC only (23). Early stages were addressed by 3 studies (stage I- IIIa (21), stage I and II (32), and stage I (34)). Three studies include all stage in their cohort (17, 29, 30). Women who received neoadjuvant chemotherapy followed by debulking surgery were exclusively selected in 7 studies (9, 14, 15, 19, 20, 28, 34). Assessment of risk of bias is summarized in Figure S1.