Clinical analysis of heterotopic ossification of bladder

Abstract

Objective To improve the understanding of heterotopic ossification (HO) of bladder. Methods The pathogenic mechanism, clinical features, diagnosis and treatment measures of the disease were reviewed and discussed with relevant literatures by analyzing the clinical data of a patient with bladder ossification. Results This patient was preoperatively diagnosed as bladder tumor, and a operation of transurethral resection of bladder tumor was performed. A nodular mass of bone-like, superior to the right ureteral orifice was found on the right lateral wall of the bladder during operation, with 3.5 cm in diameter. The pedicle of the tumor was thin, and the base was rough. Surrounding mucosa of the neoplasm was normal and no bleeding. We had to remove the tumor gradually by using a gravel pliers in that it was too hard. Postoperative pathology report revealed the main tumor as benign bladder neoplasm, which trabecular bone formation was founded in the fibrosis tissue. This patient was not treated with intravesical instillation. She was followed up for 2 years, no gross hematuria and dysuria, the general physical condition was good. Conclusions HO of bladder is rare. HO originates from osteoprogenitor stem cells lying dormant within the affected soft tissues. With the proper stimulus, the stem cells differentiate into osteoblasts and begin the process of osteoid formation, eventually leading to mature heterotopic bone formation. The diagnosis of this disease is difficult, and must be distinguished from osteosarcoma and carcinosarcoma. The determined diagnosis depends on cystoscopy and histopathological examination. The main treatment regimen is surgical resection, and the indication is similar to bladder tumor. Key words: Urinary Bladder Diseases; Osteogenesis