Introduction: Although more than 100 cases of hemangioma of the urinary bladder have been reported, capillary-type hemangiomas of the bladder are rare. Pyogenic granulomas, which are common tumor-like vascular lesions of the skin and oral mucous membranes, reveal histopathological findings similar to capillary-type hemangiomas and are differentiated from ordinary hemangiomas by clinical features and etiologic factors. Little is known regarding the occurrence of pyogenic granulomas in the urinary bladder.
Case presentation: We present the case of a 78-year-old Japanese man who had developed a hemangiomatous lesion in his bladder which led to acute clot retention. He had a recent history of chemotherapy for pancreatic cancer. A solitary pedunculated mass measuring 1.2 cm was observed in the bladder. Histopathological analysis of the resected mass revealed marked lobular capillary proliferation with surface erosions.
Conclusion: Cystoscopic and pathologic findings in addition to possible predisposing factors supported a diagnosis of pyogenic granuloma of the urinary bladder.