Suspicious peritoneal cytology refers to the result of peritoneal cytology testing that is insufficient in either quality or quantity for a definitive diagnosis of malignancy. This study examined characteristics and survival outcomes related to suspicious peritoneal cytology in endometrial cancer.
A population‐based retrospective study by querying the National Cancer Institute's Surveillance, Epidemiology, and End Results Program was conducted. A total of 41,229 women with Stage I–III endometrial cancer who had peritoneal cytologic sampling at hysterectomy from 2010 to 2016 were examined. A Cox proportional hazard regression model and a competing risk analysis with Fine‐Gray model were fitted to assess survival outcome related to suspicious peritoneal cytology.
Suspicious peritoneal cytology was seen in 702 (1.7%) cases. In multivariable models, suspicious peritoneal cytology was associated with increased risk of endometrial cancer mortality (subdistribution‐hazard ratio [HR] 1.69, 95% confidence interval [CI] 1.29–2.20, p < 0.001) and all‐cause mortality (adjusted‐HR: 1.55, 95% CI: 1.27–1.90, p < 0.001) compared with negative peritoneal cytology. Sensitivity analysis demonstrated that suspicious peritoneal cytology had discrete overall survival improvement compared with malignant peritoneal cytology in a propensity score weighting model (HR: 0.85, 95% CI: 0.72–0.99, p = 0.049).
Our study suggests that suspicious peritoneal cytology may be a prognostic factor for decreased survival in endometrial cancer.