Glomangiomyoma of Uncertain Malignant Potential in the Urinary Bladder: A Case Report

Glomus tumour typically occurs in subcutaneous tissue but rarely in the visceral organs. Most glomus tumours are benign but few atypical glomus tumours have been reported. Herein, we report a case of a 44-year-old male who presented with hematuria. Transurethral resection of bladder tumour was done. Microscopic examination showed nests and sheets of tumor around the blood vessels. Spindle cells resembling smooth muscle were also observed. An increase in mitosis was observed. These tumour cells show diffuse and strong cytoplasmic positivity for smooth muscle actin and negative for Pancytokeratin, Desmin, Synaptophysin, Chromogranin, S100, and Cluster of Differentiation 34. Ki-67 index was approximately 5%. To our knowledge, this is the first report of Glomangiomyoma of uncertain malignant potential in the urinary bladder which is considered as an unusual variant of atypical glomus tumor. This case emphasizes the importance of broad differential diagnosis which has to be considered in the urinary bladder mass.