Sebaceous Adenoma

Overview

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.

Signs & Symptoms

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. Tumors occur most commonly on the trunk, legs, feet or face. They usually cause no bothersome symptoms unless they become traumatized or secondarily infected, in which case the dog may lick or chew at the lesions.

Causes & Transmission

A benign tumor of the oil gland (sebaceous) cells of the skin. Although these tumors are commonly called “old dog warts” due to their appearance, they are not true warts as they are not viral-induced.

Affected Animals

Most common in middle aged to older dogs, especially terriers, poodles, cocker spaniels and miniature schnauzers.

Complications & Prognosis

Good, as these tumors are benign, however new tumors tend to occur as the dog ages.

Treatment

In most cases aggressive treatment is not needed, as these are cosmetic lesions. However lesions which grow, change or bother the dog should be removed and biopsied. Surgical removal is curative but new nodules often continue to form elsewhere as the dog ages. In dogs with numerous tumors, oral retinoids (ie. isotretinion) may slow growth of nodules and decrease formation of new tumors.

Diagnosis

Most commonly diagnosed by clinical presentation, but definitive diagnosis requires a biopsy, which reveals a benign accumulation of neoplastic sebaceous cells.