RESUMEN
We present here a case of malignant hemangiopericytoma in a 40-year-old female who presented with a history of slowly growing mass in left gluteal region for about 1.5 years. She was evaluated and a mass of 10 x 7.5 x 5.5 cm 3 was found on computed tomography. The tumor was resected and was sent for histopathological evaluation. Grossly the tumor was encapsulated and on cut section it was nodular. Microscopy showed spindle cells forming cords and sheets separated by thin delicate stroma consisting largely of thin-walled vessels revealed by reticulin stain. Pleomorphism and mitotic figures were seen. It was diagnosed as a case of malignant hemangiopericytoma of gluteal region. The patient underwent radiotherapy and did apparently well. She is on regular follow-up because long-term follow-up is essential in all cases as recurrence can occur several years after treatment.