Histologic confirmation of endometriosis in different peritoneal lesions

The aim of this study was to compare the macroscopic evaluation of peritoneal abnormalities suspected of endometriosis with the histologic examination of the tissue. Peritoneal biopsies from 152 patients investigated for gynecological problems (94) or undergoing tubal sterilization (58) were taken from macroscopically abnormal peritoneum, and examined for the presence of endometriosis. Endometriosis was histologically confirmed by the presence of both endometrioid glands and stroma. Endometriosis was confirmed in 78 of the patients (51%). If the diagnostic criteria were extended also to include endometrioid stroma lacking glands, but containing iron pigment and/or hemorrhage, 82 patients (54%) were positive for endometriosis. Endometriosis was histologically confirmed in 76% of pigmented lesions, in 57% of clear or red papules, in 12% of peritoneal pockets, and in 16% when only fibrosis or scarring was observed. Half of the samples with confirmed endometriosis exhibited cyclic activity. The reproducibility of the histologic evaluation was satisfactory. A high rate of negative biopsies emphasizes the need of taking biopsies from peritoneal lesions suspected of endometriosis for confirmation of the diagnosis.