Mast cell tumors are a malignant tumor that originate in the dermal layer of the skin. These tumors can arise from any area of the body, and may have a variety of appearances.
Single to multiple raised, hairless, lobulated white to pale pink skin or sometimes pigmented skin masses which may ooze an oily white material. Masses range in size from ¼” – 1” in diameter.
Affected skin is reddened, scaly, and may lose hair. With continued sun exposure thickened skin, red bumps, plaques, and nodules develop which may become ulcerated and crusty.
Lesions occur most commonly on the trunk, the legs, the digits (toe), the scrotum, the lips, the anus, and the nose. The lesions are typically ulcerated or cauliflower-like in appearance, bleed easily and are typically solitary.