Tumor in bladder reservoir after gastrocystoplasty.

PURPOSE: To our knowledge the risk of malignancy in patients with previous bladder augmentation with stomach is unknown. We report 3 cases of gastric adenocarcinoma and 1 of transitional cell carcinoma after augmentation cystoplasty with stomach with long-term followup.

MATERIALS AND METHODS: Between August 1989 and August 2002, 119 patients underwent augmentation cystoplasty with stomach at our 2 institutions (University of Miami School of Medicine, and Seattle Children's Hospital and Regional Medical Center). Medical records, urodynamic studies, radiographic imaging and laboratory evaluations were reviewed retrospectively and cases of malignancy were analyzed in detail.

RESULTS: Four male patients had carcinoma after augmentation gastrocystoplasty. Preoperative diagnosis was neurogenic bladder in 3 patients and posterior urethral valve in 1. Three patients had gastric adenocarcinoma, while the other had poorly differentiated transitional cell carcinoma. Each case progressed to malignancy more than 10 years after augmentation (11, 12, 14 and 14 years, respectively).

CONCLUSIONS: Patients who undergo bladder augmentation with a gastric remnant are at increased risk for malignancy, probably similar to that in patients with enterocystoplasty. Therefore, they require close long-term followup. Patients should be followed annually with ultrasound, and cystoscopy should be performed annually starting 10 years after gastrocystoplasty unless they have abnormal ultrasound, hematuria or another cancer risk factor. Any suspicious lesions should be biopsied, especially at the gastrovesical anastomotic site.