Laparoscopic Resection of Renal Capsular Endometriosis in a Woman with Menstrual-Related Flank Pain: Case Report

Abstract

Background: Although involvement of the urinary system is not uncommon, endometriosis in the kidneys is rare. To date, laparoscopic partial nephrectomy has been the preferred approach for managing renal endometriosis. Here, we report for the first time the results of laparoscopic removal of a renal capsular endometriosis in a malrotated kidney in an attempt to save the whole kidney parenchyma, in terms of feasibility and safety. Case presentation: A 37-year-old female presented with periodic right flank pain associated with her menstrual cycle. On imaging, a malrotated right kidney and a hypodense irregular-shaped lesion measuring 30 * 20 * 15 mm were seen in the superior portion of the right perinephric space. Histologic evaluation of the ultrasound-guided biopsy was consistent with renal capsular endometriosis. The patient underwent laparoscopic surgery to remove the capsular mass while preserving the normal renal parenchyma. Pathological examination of the biopsy obtained during surgery was in favor of renal endometriosis. At 6-month follow-up, the patient’s pain had completely disappeared and no complications had occurred. In addition, imaging did not show any remarkable recurrence. Conclusion: Renal endometriosis should be strongly considered as a differential diagnosis in female patients with a renal capsular mass and exacerbation of flank pain during menstruation. Based on our experience, with preoperative needle biopsy and clearing the pathology, laparoscopic removal of the mass in spite of renal anatomic abnormality is feasible and safe and thus could be considered as a possible treatment option.