Chemotherapy versus surgery for initial treatment in advanced ovarian epithelial cancer

Epithelial ovarian cancer presents at an advanced stage in the majority of women. These women require surgery and chemotherapy for optimal treatment. Conventional treatment has been to perform surgery first and then give chemotherapy. However, there may be advantages to using chemotherapy before surgery.

To assess whether there is an advantage to treating women with advanced epithelial ovarian cancer with chemotherapy before debulking surgery (neoadjuvant chemotherapy (NACT)) compared with conventional treatment where chemotherapy follows debulking surgery (primary debulking surgery (PDS)).

We searched the following databases on 11 February 2019: CENTRAL, Embase via Ovid, MEDLINE (Silver Platter/Ovid), PDQ and MetaRegister. We also checked the reference lists of relevant papers that were identified to search for further studies. The main investigators of relevant trials were contacted for further information.

Randomised controlled trials (RCTs) of women with advanced epithelial ovarian cancer (Federation of International Gynaecologists and Obstetricians (FIGO) stage III/IV) who were randomly allocated to treatment groups that compared platinum-based chemotherapy before cytoreductive surgery with platinum-based chemotherapy following cytoreductive surgery.

Two review authors independently extracted data and assessed risk of bias in each included trial.

We found 1952 potential titles, with a most recent search date of February 2019, of which five RCTs of varying quality and size met the inclusion criteria. These studies assessed a total of 1713 women with stage IIIc/IV ovarian cancer randomised to NACT followed by interval debulking surgery (IDS) or PDS followed by chemotherapy. We pooled results of the three studies where data were available and found little or no difference with regard to overall survival (OS) (1521 women; hazard ratio (HR) 1.06; 95% confidence interval (CI) 0.94 to 1.19, I² = 0%; moderate-certainty evidence) or progression-free survival in four trials where we were able to pool data (1631 women; HR 1.02; 95% CI 0.92 to 1.13, I² = 0%; moderate-certainty evidence). Adverse events, surgical morbidity and quality of life (QoL) outcomes were poorly and incompletely reported across studies. There may be clinically meaningful differences in favour of NACT compared to PDS with regard to serious adverse effects (SAE grade 3+). These data suggest that NACT may reduce the risk of need for blood transfusion (risk ratio (RR) 0.80; 95% CI 0.64 to 0.99; four studies,1085 women; low-certainty evidence), venous thromboembolism (RR 0.28; 95% CI 0.09 to 0.90; four studies, 1490 women; low-certainty evidence), infection (RR 0.30; 95% CI 0.16 to 0.56; four studies, 1490 women; moderate-certainty evidence), compared to PDS. NACT probably reduces the need for stoma formation (RR 0.43, 95% CI 0.26 to 0.72; two studies, 581 women; moderate-certainty evidence) and bowel resection (RR 0.49, 95% CI 0.26 to 0.92; three studies, 1213 women; moderate-certainty evidence), as well as reducing postoperative mortality (RR 0.18; 95% CI 0.06 to 0.54:five studies, 1571 women; moderate-certainty evidence). QoL on the EORTC QLQ-C30 scale produced inconsistent and imprecise results in two studies (MD -1.34, 95% CI -2.36 to -0.32; participants = 307; very low-certainty evidence) and use of the QLQC-30 and QLQC-Ov28 in another study (MD 7.60, 95% CI 1.89 to 13.31; participants = 217; very low-certainty evidence) meant that little could be inferred.

The available moderate-certainty evidence suggests there is little or no difference in primary survival outcomes between PDS and NACT. NACT may reduce the risk of serious adverse events, especially those around the time of surgery, and the need for bowel resection and stoma formation. These data will inform women and clinicians and allow treatment to be tailored to the person, taking into account surgical resectability, age, histology, stage and performance status. Data from an unpublished study and ongoing studies are awaited.