Cytoreductive surgery (CRS) feasibility and the need for extensive surgery in patients with advanced ovarian cancer are difficult to assess. Therefore, it will be helpful to identify patients for CRS in a precise manner using preoperative and intraoperative criteria. This research aimed to establish if there is a correlation between the number of peritoneal metastases found during surgery, the degree of completion of interval CRS, and survival. Patients with newly diagnosed stage III-IV epithelial ovarian cancer who received neoadjuvant chemotherapy followed by interval CRS were included in this single-center observational cohort research. 

During resecting the abdomen, the 7 Region Count (7RC) was taken to accurately and reliably measure the number of metastases found in the peritoneal cavity. Surgical outcomes were predicted using logistic regression analysis, and survival times were analyzed using Cox regression. The final count for those who were analyzed was 316. The most common 7RC was 4. (interquartile range: 2–6). About 58% of patients underwent full CRS, 30% underwent optimal CRS, and 12% underwent just partial CRS. In multivariate analysis, reduced odds of full or optimal CRS were seen in patients with a greater 7RC (odds ratio [OR] = 0.45, 95% confidence interval [CI]: 0.33-0.63, P < 0.001). 

The same was true for progression-free survival (hazard ratio [HR] = 1.17, 95% CI 1.08-1.26, P < 0.001) and overall survival (HR = 1.14, 95% CI 1.04-1.25, P = 0.007): a greater 7RC was independently linked with worse outcomes for both. In addition to predicting whether or not CRS would be achieved, the amount of peritoneal metastases, as reflected by the 7RC during surgery, also provides independent prognostic significance for progression-free survival and overall survival.