Angiomyofibroblastoma-like tumor of scrotum
Angiomyofibroblastoma-like tumor of the scrotum is a rare, well-defined, slow growing mesenchymal extratesticular nonepididymal tumor rarely seen in the perineum or scrotum of older male patients. A similar tumor can occur in females in the vulval region.
Epidemiology
In males, they are seen in middle aged to elderly patients between age 45 and 75. In the majority of cases it has an indolent and nonaggressive clinical course; however, focal invasion and recurrence have been reported.
Pathology
Macroscopic appearance
These tumors appear as superficial well-circumscribed masses with a grayish white to yellowish brown color.
Microscopic appearance
Angiomyofibroblastoma-like tumors of the scrotum demonstrate high vascularity and perivascular fibrinoid hyalinisation. The tumor cells are spindle cells with minimal atypia and a low mitotic rate. A small amount of fat is seen in 25-56% of cases.
Immunophenotype
Positive for vimentin and negative for S100, actin, and CD34.
Radiographic features
Ultrasound
Heterogeneous echotexture, isoechoic to the surrounding tissue and subcutaneous fat.
CT
Well-circumscribed homogeneous subcutaneous oval mass, possibly with several small internal hypodense foci.
MRI
- T1: low due to high fibrous content
- T2: intermediate heterogeneous signal
Intense postcontrast enhancement due to high vascularity of the lesions.
Treatment
Treatment is wide surgical resection to reduce recurrence rate.
Differential diagnosis
In the scrotum, the differential includes rare lesions such as:
- spindle lipoma of the scrotum
- liposarcoma of the scrotum
- solitary fibrous tumor of the scrotum
- leiomyoma of the scrotum
- aggressive angiomyxoma of the scrotum