Photo Credit: unomat

The following is a summary of “Survival outcomes of primary vs interval cytoreductive surgery for International Federation of Gynecology and Obstetrics stage IV ovarian cancer: a nationwide population-based target trial emulation,” published in the February 2025 issue of Obstetrics and Gynaecology by Jochum et al. 

The optimal surgical approach (primary vs interval cytoreductive surgery) for stage IV ovarian cancer (OC) remains unclear and may depend on disease extent.   

Researchers conducted a retrospective study to analyze the effect of primary vs interval cytoreductive surgery on progression-free (PFS) and overall survival (OS) in patients with International Federation of Gynecology and Obstetrics stage IV OC using target trial emulation.  

They performed a target trial using the French national health insurance database to examine the causal effects of primary vs interval cytoreductive surgery on stage IV OC prognosis (Surgery for OC FIGO 4: SOFI-4). The clone method with inverse probability of censoring weighting was applied to adjust for informative censoring and balance baseline characteristics between groups. Subgroup analyses were performed based on stages and extraperitoneal metastasis locations. Patients younger than 75 years, in good health, and diagnosed with stage IV OC between January 1, 2014, and December 31, 2022, were included. The primary outcome was 5-year PFS, and the secondary outcome was 7-year OS.   

The results showed that among 2,772 patients, 948 (34.2%) had stage IVA and 1,824 (65.8%) had stage IVB OC, of these, 1,182 (42.6%) underwent primary cytoreductive surgery, and 1,590 (57.4%) received interval cytoreductive surgery. Median PFS was 19.7 months (interquartile range, 19.3–20.1) for primary cytoreductive surgery, compared to 15.7 months (interquartile range, 15.7–16.1) for interval cytoreductive surgery. Median OS was 63.1 months (interquartile range, 61.7–65.4) for primary cytoreductive surgery and 55.6 months (interquartile range, 53.8–56.3) for interval cytoreductive surgery. Primary cytoreductive surgery resulted in a 5.0-month increase in 5-year PFS (95% confidence interval (CI), 3.8–6.2) and a 3.9-month increase in 7-year OS (95% CI, 1.9–6.2). These survival benefits were consistent across stage IVA and IVB subgroups and were notable in patients with pleural, supradiaphragmatic, or extra-abdominal lymph node metastasis. 

Investigators concluded that primary cytoreductive surgery offered benefits over interval cytoreductive surgery for stage IV OC. 

Source: sciencedirect.com/science/article/pii/S0002937824008184