Significance of peritoneal washing cytology in the accurate staging of malignant ovarian tumors

Objectives: To identify the percentage of ovarian cancers with positive peritoneal cytology and to correlate the positive cytology with the prognostic factors.

Methods: This retrospective, cross-sectional study, evaluated the data of surgical specimens of malignant ovarian tumors, received in the Department of Pathology, Dow University of Health Sciences over a period of three years. The peritoneal cytology was correlated with these prognostic parameters: the size of the tumor, stage, capsular invasion, omental, and lymph node metastasis.

Results: Eighty malignant ovarian tumors were diagnosed. Serous carcinoma was the most common ovarian tumor, diagnosed in 24 (30.0%) cases, followed by endometrioid carcinoma in 17 (21.25%) and Granulosa cell tumor in 11 (13.75%) cases. The mean age of the patients was 41.91 years (range 7-71 years). The mean size of the tumors was 10.03 cm (SD 5.62 cm). The ovarian capsular invasion was present in 27 (33.75%) tumors. Peritoneal cytology was positive in 10/24 cases, with a detection rate of 41.66%. Omentum was involved in 12/34 (35.29%) cases. Lymph node dissection was performed in three cases, two were reported as positive for metastasis. Peritoneal cytology significantly correlated with the tumor size (p=0.045), and with ovarian capsular invasion (p=0.054) and omental metastasis (p=0.052). Most of the tumors were staged as FIGO stage IA.

Conclusion: Peritoneal cytology correlates with the tumor size, stage, and omental metastasis of the malignant ovarian tumors. It should be routinely performed at the time of surgery for the optimal staging of the patients.