Peritoneal washing cytology in patients with BRCA1 or BRCA2 mutations undergoing risk-reducing salpingo-oophorectomies: A 10-year experience and reappraisal of its clinical utility

Objective: To evaluate the utility of peritoneal washing cytology (PWC) for detecting occult primary peritoneal carcinoma in patients with BRCA1 or BRCA2 mutations, we reviewed PWCs obtained during risk-reducing salpingo-oophorectomy (RRSO) from 117 patients at our institution and correlated the results with surgical pathology findings. Methods: Records of 128 PWCs from 125 patients with BRCA1 or BRCA2 mutations undergoing RRSO at MD Anderson Cancer Center between 2000 and 2010 were obtained. Slides were available for review for 119 PWCs from 117 patients (2 patients had 2 PWCs each). Cytopathologists, blinded to the RRSO histopathologic diagnoses, categorized the PWCs as benign, atypical, suspicious for malignancy, or malignant. These results were correlated with the RRSO histopathologic diagnoses. Results: PWCs from 113 patients were benign. Of the remaining 4 patients, 2 had PWCs classified as atypical, 1 as suspicious for malignancy, and 1 as malignant. The corresponding RRSO histopathologic findings of the 2 atypical PWCs showed endosalpingiosis and cystadenofibroma in one case and showed no abnormalities in the other case. Both patients with suspicious or malignant PWCs, indicating the possibility of occult peritoneal carcinoma, had RRSO histopathologic diagnoses of endometriosis and endosalpingiosis. Nine patients had abnormal tubal or ovarian histologic findings, but all 9 of these patients had benign PWCs. Conclusion: PWC has the potential to detect occult peritoneal carcinoma in patients with BRCA1 or BRCA2 mutations. The clinical significance of a positive PWC without abnormal RRSO histology remains unclear and will require long-term follow-up for determination.