Malignant proliferating trichilemmal tumor in abdominal wall: Report of a rare case at an uncommon site with literature review.

The proliferating trichilemmal tumor (PTT) is a very rare cutaneous neoplasm that rarely is malignant. PTTs mainly occur in the scalp of elderly women. Only 10% occur in places other than scalp. We present a 62-year-old male patient with malignant PTT in his abdominal wall.