Positive Peritoneal Cytology as a Predictor of Prognosis in Early Stage of Endometrioid Adenocarcinoma

Background: Peritoneal cytology has been reported to be an independent risk factor for poor survival, but it is not included in the current international federation of gynecology and obstetrics (FIGO) staging system for risk stratification. Objectives: We aimed to investigate the prognostic significance of positive peritoneal cytology (PPC) in patients with early stage endometrioid adenocarcinoma. Methods: Medical profiles of patients with uterine carcinoma referring to Imam Khomeini hospital and Mirza Koochak Khan hospital between September, 2005 and December, 2011 have been reviewed. Patients had a complete staging procedure and peritoneal cytology evaluation. Results: Among 220 patients with mean age of 56.3 ± 9.1 years, 204 were Negative for peritoneal cytology (NPC) and 16 showed PPC. In the group of patients with endometrioid adenocarcinoma, 125 were in stage I and 32 were in stage II. Univariate analysis on patients with endometrioid adenocacinoma revealed that stage II (OR = 7.12, 95% CI = 2.95-22.10, P value < 0.001), stage III (OR = 8.04, 95% CI = 2.14 - 30.09, P value < 0.001), stage IV (OR = 58.09, 95% CI = 13.74 - 245.66, P value < 0.001), recurrence of either intra (OR = 32.65, 95% CI = 12.2 - 86.7, P value < 0.001) or extra pelvic (OR = 14.54, 95% CI = 4.4 - 47.7, P value < 0.001), and the number of lymph nodes involvement (OR = 5.59, 95% CI = 2.5 - 12.51, P value < 0.001) were significantly associated with survival. Also, patients with PPC had significantly poorer survival compared to those with negative peritoneal cytology; 38% Vs 88% were alive after 5 years (P value < 0.0001). Mean 5-year survival in PPC and NPC patients were 3.31 years and 4.74 years, respectively. Conclusions: Our study demonstrated that positive peritoneal cytology is an independent prognostic factor in patients with early stage endometrioid adenocarcinoma. We propound that peritoneal cytology adds back into the future FIGO staging criteria revision. Until then, peritoneal washings should still be considered as an important part for accurate risk-stratification.