Histologic appearance of endometriosis infiltrating uterosacral ligaments in women with painful symptoms

Study Objective. To describe the histologic appearance of deep endometriosis infiltrating the uterosacral ligaments (USL). Design. Retrospective analysis (Canadian Task Force classification II-2). Setting. University-affiliated hospital. Patients. One hundred forty-nine women with pain due to endometriosis. Intervention. Resection of one or both USL. Measurements and Main Results. One hundred seventy-two USL were examined by histology after unilateral resection in 126 patients (84.6%) and bilateral resection in 23 (15.4%). Two-thirds of women (122, 70.9%) had a classic appearance of endometriosis. Lesions of myoproliferative endometriosis with a histologic appearance of so-called adenomyotic nodules were observed in 25 (14.5%). Associated fibrosis was most frequent in patients with positive compared with negative histology (85, 69.7% vs 18, 36.0%). Conclusion. Anatomicopathologic lesions of deep endometriosis infiltrating the USL are heterogeneous. Adenomyotic nodules are not frequently observed.