Histopathologic Analysis of Intestinal Endometriosis after Laparoscopic Low Anterior Resection

Study ObjectiveTo determine how intestinal endometriosis spreads, and, thus, to improve outcomes of curative surgery.DesignDescriptive study (Canadian Task Force classification II-2).SettingUniversity hospital.PatientsTen patients who underwent laparoscopic low anterior resection of intestinal endometriosis at our hospital between January 1999 and August 2007.InterventionLaparoscopic low anterior resection of intestinal endometriosis.Measurements and Main ResultsMapping of endometriotic foci, degree of vertical infiltration to the intestinal layers, and longitudinal spread of endometriotic foci to the intestinal plane were defined using hematoxylin-eosin, estrogen receptor, progesterone receptor, and CD10 staining.ResultsEndometriotic foci tended to spread concentrically around a primary lesion that comprised most of a resected specimen. The deepest layer containing endometriotic foci at the primary lesion was the submucosal layer in 7 specimens (70%), and the internal circular muscle layer in 3 (30%). Satellite lesions comprising thickened areas that were independent of the primary lesion were detected in 5 specimens (50%). Multiple endometriotic foci were confirmed in all satellite lesions.ConclusionsEndometriotic foci might not only infiltrate the primary lesion in intestinal endometriosis but also disseminate to other areas. Thus, the primary lesion of intestinal endometriosis with a large margin must be excised via low anterior resection.