False positive malignant peritoneal cytology and psammoma bodies in benign gynecologic disease.

OBJECTIVE: To determine the incidence of false positive malignant peritoneal cytology and psammoma bodies associated with benign gynecologic disorders. STUDY DESIGN: Pelvic peritoneal fluid was prospectively collected for cytologic examination from 119 women undergoing laparoscopy for benign conditions (infertility, 67; pelvic pain, 35; elective sterilization, 17). The median age was 30. No patient had laparoscopic gross cancer or histologic evidence of cancer. RESULTS: The peritoneal cytology of 2 of 119 cases (2%) contained cells with features suggestive of malignancy, and 6 of 119 cases (5%) contained psammoma bodies. Both cases of false positive peritoneal cytology and four of six with psammoma bodies were associated with endometriosis. All cases were followed for a minimum of two years, and no patient had developed cancer. CONCLUSION: Peritoneal fluid from cases of benign gynecologic disorders, especially endometriosis, can contain psammoma bodies and cells suggestive of malignancy.