A Rare Case of Bladder Endometriosis Mimicking a Bladder Tumor

The presence of endometrial stroma and/or glandular epithelium in organs other than the uterus is called endometriosis. Urinary system endometriosis is observed in approximately 1% of women with endometriosis and is most commonly seen in the bladder. A 27-year-old female patient was admitted to the urology clinic with cyclic complaints of painful and frequent urination. Ultrasonography revealed a lesion extending to the lumen of approximately 15x10 mm in the left side wall of the bladder. On cystoscopy, a suspicious area with irregular borders was observed, approximately 15 mm, at the left-posterior lateral wall of the bladder, and transurethral resection was performed. The pathological result of the patient was reported as bladder endometriosis. Although rare, bladder endometriosis should be considered in the differential diagnosis, especially in women of reproductive age with cyclic urological complaints.