PEDIATRIC UROLOGY

Long-term follow up of enteric bladder augmentations: the risk for malignancy
Husmann DA, Rathbun SR
Department of Urology, Mayo Clinic, Rochester MN 55905, USA
J Pediatr Urol. 2008; 4: 381-5; discussion 386

• Objective: To determine the risk of bladder cancer following enteric bladder augmentation.
• Materials and Methods: Patients followed for care after an enteric bladder augmentation have been entered into a registry; individuals followed for a minimum of 10 years were evaluated.
• Results: The study criteria were met by 153 patients. Indications for bladder augmentation were neurogenic bladder in 97, exstrophy in 38 and posterior urethral valves in 18. There was a median follow-up interval of 27 years (range 10-53). A total of seven cases of malignancy developed. Median time to tumor development following augmentation was 32 years (range 22-52). Two patients with neurogenic bladder developed transitional cell carcinoma; both were heavy smokers (> 50 pack per year history). Two patients with a history of posterior urethral valves and renal transplantation developed adenocarcinoma of the enteric augment. Three patients with bladder exstrophy developed multifocal adenocarcinoma of the augmented bladder. Two patients remain alive, 5 and 6 years following radical cystoprostatectomy; five died of cancer-specific causes.
• Conclusions: Malignancy following enteric bladder augmentation arose in 4.5% (7/153) of our patients and was associated with coexisting carcinogenic stimuli (prolonged tobacco/chronic immunosuppressive exposure), or alternatively with the inherent risk of malignancy existing with bladder exstrophy.
  
  
• Editorial Comment
  From 1986 to 2007, 153 patients who had greater than 10 years follow up for enterocystoplasties were studied. No patient in the study had a mixture of feces and urine prior to the enterocystoplasty, only patients who were augmented due to neurogenic bladder, exstrophy/epispadias complex or posterior urethral valves were included. The mean follow up was 27 years with a range of 10-53. Seven cases of malignancy occurred. There was no correlation with malignancy and recurrent urinary tract infections. There was no difference in cancer in the ilia or colonic segments. The incidence of asymptomatic bacteriuria did not reach statistical significance. 2 patients who developed cancer had heavy smoking histories. 2 patients developed cancer after prolonged immunosuppression after renal transplantation, and 3 patients in the exstrophy/epispadias group developed multi-focal adenocarcinoma involving the bladder and enteric segments. The study points out that in other countries where schistosomiasis or tuberculosis are common, enterocystoplasty cancers are found frequently. Most of the previous studies do not have a long enough follow up to have any tobacco use history be a significant risk factor. The cancer risk demonstrated in this paper is 4.5%, which is greater than the previous series of 0.6%-2.8%.
  This paper reminds us that these patients need continual follow up throughout their adult lives. It was cancer risk in this same range that discouraged urologists from performing ureterosigmoidostomies and I believe this same risk will produce new solutions to the bladder dysfunction that has been an indication for enterocystoplasties in the past.

Dr. Brent W. Snow
Division of Urology
University of Utah Health Sci Ctr
Salt Lake City, Utah, USA
E-mail: brent.snow@hsc.utah.edu