Papillomas, Lipomas, Cysts, and Basal Cell Tumors in Dogs
Epidermal Inclusion Cysts (Sebaceous Cysts)
Epidermal inclusion cysts, also called sebaceous
cysts, are common surface tumors found anywhere on the body. Kerry Blue
Terriers, Schnauzers, Poodles, and spaniels are most often affected. Epidermal
inclusion cysts begin when dry secretions block hair follicles, causing an
accumulation of hair and sebum (a cheesy material), and the subsequent
formation of a cyst.
These cysts produce a dome-shaped swelling up to an inch or more in size
beneath the skin, though most are smaller. They can become infected and may
need to be surgically drained. This sometimes leads to a cure.
Treatment: Surgical excision is the treatment of choice, although it is not
A lipoma is a benign growth made up of mature fat cells interlaced with
fibrous connective tissue. Lipomas are common in overweight dogs, especially
females. A lipoma can be recognized by its oblong or round appearance and
smooth, soft, fatlike consistency. Lipomas grow slowly and may get to be
several inches in diameter. They are not painful. Rarely, what appears to be a
lipoma is a malignant variant called a liposarcoma.
Treatment: Surgical removal is necessary if the lipoma is interfering with
the dog’s mobility, is growing rapidly, or is cosmetically
bothersome. The tumor should be biopsied if there is any question about the
Histiocytomas are rapidly growing tumors found in dogs 1 to 3 years of age.
They occur anywhere on the body. These benign tumors are dome-shaped, raised,
hairless surface growths that are not painful. Because of their appearance,
they are often called button tumors. These benign growths are more common on
Treatment: Most histiocytomas disappear spontaneously within one to two
months. Those that persist should be removed for diagnosis.