Paraganglioma of the urinary bladder: can biologic potential be predicted?

BACKGROUND: Paraganglioma of the urinary bladder is rarely encountered and its biologic behavior is uncertain. The authors sought to determine the prognostic factors that would predict patient outcome.

METHODS: The Mayo Clinic experience over 53 years with paraganglioma of the bladder was reviewed. All histologic slides from 16 patients were reviewed by the authors. Eight cases were examined immunohistochemically with cytokeratin (AE1/3, cytokeratin 7, and cytokeratin 20), vimentin, S-100 protein, neuroendocrine markers (chromogranin, synaptophysin, and neuron specific enolase), p53 protein, and MIB-1. DNA ploidy was determined by digital image analysis in formalin fixed, paraffin embedded tissue. The mean follow-up was 6.3 years (range, 0.4-16.4 years).

RESULTS: Paraganglioma usually occurred in young adult women (mean age, 45 years; range, 16-74 years). The male-to-female ratio was 1 to 3. The common symptoms and signs were hypertension and hematuria. The tumors were usually located intramurally in the lateral and posterior wall of the bladder and were multifocal in 3 cases (18%). Seven patients were treated by transurethral resection, eight by partial cystectomy, and one by radical cystectomy. T classification was T1 (1 patient), T2 (9 patients), T3 (2 patients), and T4b (4 patients). At the time of diagnosis, one patient had distant metastasis and one had regional lymph node metastasis. One patient developed metastasis 1 year after diagnosis and died of the disease 1.5 years later. None of the patients with T1 or T2 tumors had recurrence or tumor progression. All tumors were aneuploid. The mean MIB-1 labeling index was 1.5% (range, 0.03-7.0%). The tumor cells displayed immunoreactivity for S-100 protein and neuroendocrine markers and were negative for p53 (except 1 case) and cytokeratin.

CONCLUSIONS: Paraganglioma of the urinary bladder occurs mostly in young adult women. Patients with tumor of advanced classification (>/=T3) are at risk of recurrence, metastasis, and dying of the disease, whereas patients in this study with T1 or T2 disease had favorable outcomes after complete tumor resection.