S2k guidelines for the diagnosis and treatment of endometriosis-Recommendations for pathology

The present article summarises the recommendations for the handling, histopathological workup, diagnostics and reporting in surgical pathology of biopsies and resection specimens in patients with the clinical diagnosis of endometriosis. In addition to practical aspects of pathology, the guidelines also take into account the clinical requirements for histopathology for the optimal diagnosis and therapy of the patients. Based on the definition of endometriosis of the corpus uteri (adenomyosis uteri) most commonly used in the pathological literature, this was defined in the guidelines as the detection of the endometriosis focus in the myometrium at a distance from the endomyometrial border of a medium-sized visual field (100x magnification), which in metric units corresponds to around 2.5 mm. In bowel resection specimens, the status of the resection margins had to be documented within the histopathological report. Also mentioned are the requirements for the reporting of carcinomas associated with endometriosis, including the immunohistochemical evaluation of steroid hormone receptors and mismatch repair proteins.