尿管endometriosisについて

A 23-year-old woman first visited the medical clinic with chief complaint of flank pain on the left, where she was diagnosed as ureteral stone and referred to the urology department. IVP revealed hydronephrosis and dilatation of the upper two thirds of the ureter on the left. The opposite side showed normal upper urinary tract. Ureteral catheterization met obstruction at 10 cm from the ureteral orifice, therefore retrograde pyelography was unsuccessful. Prove operation was carried out, and a periureteral mass was found. The ureter was released from the mass and stenosis was completely relieved. The mass was histopathologically endometriosis.