Repeat spontaneous bladder rupture following radiation therapy.

Spontaneous rupture of the native bladder is a rare occurrence. Episodes have been reported in adults following pelvic radiation therapy for gynecological and urological malignancies. We report a case of repeat spontaneous bladder rupture in a pediatric patient following radiation therapy for rhabdomyosarcoma of the bladder. CASE REPORT A 12-year-old female presented with abdominal pain, nausea and vomiting, and minimal urine output 48 hours in duration. The patient had a history of rhabdomyosarcoma of the bladder diagnosed at age 1 year, and had been treated using the Intergroup Rhabdomyosarcoma Study Group protocol with partial cystectomy, chemotherapy and external beam radiation therapy. She was disease-free since completing therapy but had been treated for 2 previous spontaneous bladder ruptures elsewhere, by open repair at age 4 years and conservatively by catheter drainage at age 10 years. She reported no recent changes in voiding habits leading up to the acute complaints, but had a long-standing history of urinary frequency after cancer therapy. Physical examination was notable for a distended abdomen that was diffusely tender. A catheter was placed with minimal return of urine. Serum creatinine was increased at 6.2 mg/dl (normal 0.4 to 1.2). Computerized tomography of the abdomen and pelvis demonstrated a large amount of free intraperitoneal fluid, and computerized cystography showed intraperitoneal extravasation of contrast material. The patient underwent exploratory laparotomy with evacuation of intra-abdominal urine and repair of a 1 1c m perforation on the anterior bladder wall near the dome. Biopsy of the region surrounding the perforation revealed chronic inflammation, necrosis and fibrosis consistent with previous radiation with no evidence of malignancy. On postoperative day 1 serum creatinine was 0.7 mg/dl and postoperative course was uneventful. She was scheduled for urodynamic evaluation and recommended for continent urinary diversion but was lost to followup. DISCUSSION Radiation therapy can affect the bladder directly, as in the case of treatment for transitional cell carcinoma or rhabdomyosarcoma, or as a result of proximity effect of treatment for cervical or prostate cancer. Well described complications from radiation therapy include cystitis, hematuria and fistula formation. Less common is bladder rupture, which has occurred in adults following radiation treatment for cervical and bladder carcinoma.1 To our knowledge we report the first case of spontaneous rupture of a native bladder following radiation therapy in a pediatric patient, as well as the first case of rupture following radiotherapy for rhabdomyosarcoma. Radiation therapy induces a wide spectrum of pathological changes in the bladder. Abnormalities (including inflammatory infiltrates, fibrosis, cellular atypia and necrosis) may be found in all layers of the bladder wall, as well as in the vasculature. These alterations may contribute to structural weakness that predisposes the irradiated bladder to spontaneous perforation. Other pathological conditions such as bladder outlet obstruction, recurrent tumor and neurological disease affecting urine storage or emptying should be considered as possible contributing factors, although none of these conditions was present in our patient. The fact that our patient also underwent partial cystectomy could be an additional contributing factor to the episodes of spontaneous rupture if radiation further weakened the region of postoperative scarring. However, this determination could not be made conclusively by either gross or histological examination of the region of perforation. In adults the timing of these perforations has been reported as remotely as 15 years following treatment, and repeat episodes are known to occur and should be considered in the acute setting.2 Our case also emphasizes the need for urological assessment of outcomes from current bladder sparing therapies for rhabdomyosarcoma. To our knowledge this patient never underwent evaluation of the voiding dynamics after completion of therapy, but rather was only seen by urologists emergently during episodes of bladder rupture. Recent reports from the Intergroup Rhabdomyosarcoma Study3 emphasize apparent success in preserving the bladder but the functional status of the bladder has not been documented by urologists, and presumably our patient had been considered successfully treated.