Surgically treated bladder hemangiopericytoma/solitary fibrous tumor: report of a 12-year asymptomatic follow-up.

Hemangiopericytoma (HPC)/solitary fibrous tumor (SFT) is an uncommon vascular tumor suggested to be originating from pericytes. There are few reports on bladder HPC/SFT. We present a case of huge bladder HPC/SFT measuring 13.9 × 12.2 × 11.1 cm with invasion to right iliac vein in a 54-year-old man. The patient underwent radical surgical tumor excision without chemotherapy or radiotherapy. The patient is symptom-free without recurrence or metastasis during the 12-year follow-up period. This case is the longest follow-up reported to date for bladder HPC/SFT.