Kojima N, et al. - Between January 2007 and May 2018, 110 patients with ovarian/tubal/primary peritoneal high-grade serous carcinoma (HGSC, the most common subtype of ovarian cancer that accounts for 70%-80% of ovarian cancer deaths) were recruited by the researchers in order to assess whether peritoneal washing cytology (PWC) during interval debulking surgery (IDS) could foretell the prognosis of patients with HGSC achieving R0 status. The survival outcomes were contrasted among the PWC-positive and PWC-negative groups. Seventeen months of the median progression-free survival (PFS) for the entire cohort was observed. when compared to the PWC-negative group, the median PFS for the PWC-positive group was markedly shorter. On both univariate and multivariate analyses, including age and FIGO stage, elevated risk of progress was recognized. Therefore, in patients with pelvic HGSC, the positive PWC during IDS was found to forecast earlier disease recurrence accomplishing R0 status. Furthermore, prospective validation should be conducted in the future, when conducting PWC during IDS become standard practice.