Long-term follow up of enteric bladder augmentations: the risk for malignancy.

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.