Papillomas, Lipomas, Cysts, and Basal Cell Tumors in Dogs
Skin tumors are common in dogs. It is often impossible to determine whether a skin tumor is benign or
malignant by appearance alone. The only conclusive way to make a diagnosis is
by biopsy, a procedure in which tissue or cells are removed by your
veterinarian and examined under a microscope by a veterinary pathologist.
For small tumors it is best for your veterinarian to remove the growth and
present the entire specimen to the pathologist. For tumors larger than 1 inch
(2.5 cm) across, it may be advisable for your veterinarian to obtain a tissue
sample by fine needle aspiration. In this procedure, a needle connected to a
syringe is inserted into the tumor and cells are obtained by pulling back on the
plunger. Alternatively, the vet can use a cutting needle to obtain a core
sample. An open biopsy, in which an incision is made, is preferred for
suspected sarcomas and tumors that present diagnostic problems for the
Estrus, or heat, is the stage in a female dog's reproductive cycle during which she becomes receptive to mating with males. At this time, estrogen levels first increase and then sharply decrease, and mature eggs are released from the ovaries. Ideally, your dog should be spayed before she enters her first heat cycle.
Skin papillomas are benign wartlike growths that occur on the skin of the
body, on the foot pads, and beneath the nails. They are caused by the canine
oral papilloma virus and tend to occur in older dogs, especially older
Treatment: They do not need to be removed unless they are causing a problem
because of their location on the body. Rarely, these will become injured and
bleed or get infected. In these cases, removal is recommended.
A hematoma is a blood clot beneath the skin, caused by a blow or contusion.
These are not cancers. Large ones may need to be drained. Ear
flap hematomas require special attention (see Swollen Pinna).
Calcifying hematomas are hard masses that resemble bone. They tend to occur
at fracture sites, and may be found as a bump on the skull of a tall dog who
strikes her head on the underside of the dining room table.
Treatment: Calcifying hematomas do not need be removed but may have to be
biopsied if there is a question of bone tumor. They are difficult to treat and
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