ABSTRACT

Glomus tumor is a mesenchymal tumor that results from differentiation of modified smooth muscle cells responsible of thermoregulation. They account for <2% of soft tissue tumors. Although these tumors are found in all body parts, 80% of them are placed in the upper extremities and 75% of them are located beneath finger nails. Malignant glomus tumor, which mostly shows local infiltration, is very rare accounting for 1% of total glomus tumors. Our case, which describes a malignant glomus tumor localized in patella, is presented and discussed because of its rare location and posttreatment recurrence