Neurofibromatosis involving the urinary bladder.

We present two interesting cases of a 24-year-old man and a 14-year-old boy, uncle and nephew, with lower urinary tract symptoms, café au lait patches and subcutaneous nodules. Ultrasonography and computed tomography scans showed a large, irregular lobulated soft tissue mass between the bladder and sacrum. Cystoscopy, laparotomy and biopsies revealed neurofibromatosis involving the urinary bladder. No enlargement of the tumor or upper urinary tract obstruction has occurred during the long-term follow up. We recommend meticulous follow up of patients with giant intrapelvic neurofibromatosis.