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Lumps and Bumps on your pets

Posted by lhvs on June 2, 2016

Sebaceous Cyst
Wart & Skin Tag
Squamous Cell Carcinoma
Transitional Cell Carcinoma
Mast Cell Tumor 
Mammary Carcinoma
Basal Cell Tumor

Lumps & Bumps on Your Pets

Dogs and cats can develop lumps and bumps on their skin. Skin lumps are a common condition veterinarians are faced with. Sounds simple, but determining what they are can be tricky. If you find a lump on your pet, it is important to contact your veterinarian.

The lipoma (fatty tumor) is one of the most commonly encountered lump.

  • Fat deposits under the skin
  • Soft, round, non-painful masses
  • Occasionally found between muscles
  • Generally benign (not cancerous)
  • They tend to stay in one place
  • Don’t tend to invade other surrounding tissues
  • Some may cause discomfort depending on location
  • Most do not have to be removed
  • Removal is only necessary if the lipoma is interfering with the dog’s mobility, is growing rapidly, or is cosmetically bothersome

A sebaceous cyst is a blocked oil gland that looks like a pimple. When it bursts, a white, pasty material comes out. They are basically large pimples!

  • Common benign surface tumors
  • Terriers, Schnauzers, Poodles, and spaniels are most often affected
  • Begin when something blocks a pore on skin and results in a “clogged” oil gland
  • Dome-shaped swelling
  • Become infected and may need to be drained
  • Some burst on their own leaving a white, brown, or cottage cheese like discharge
  • Antibiotics, anti-inflammatory drugs, or other medications may be recommended


Because of their appearance histiocytomas are often called “button tumors”.

  • Benign
  • Rapidly growing tumors
  • Usually found in dogs 1 to 3 years old
  • More common in short haired dogs
  • Dome-shaped, raised, hairless surface growths that are not painful
  • Most of these tumors disappear within 1 to 2 months
  • Any that persist should be examined further by your veterinarian


Warts and skin tags are pesky yet painless bumps that can develop on various parts of your pet’s body.

  • Benign tumors on the surface of the skin
  • Mostly seen on older dogs
  • Can be more of a problem on dogs that get groomed (clippers may cut the wart and cause bleeding)


Squamous cell carcinomas can develop on the skin and inside the mouth.

  • Tumors that affect the tonsils or tongue are difficult to remove and can grow quite large
  • Oral squamous cell carcinomas are very aggressive (less than 10% of dogs with tumors in these locations survive to 1 year after diagnosis)

Lymphoma is among the most common type of tumor seen in dogs.

  • Represents 20% of all canine cancers
  • Dogs are 2 – 5 times more likely to get lymphoma than humans
  • Golden Retrievers are more likely effected
  • Enlargement of lymph nodes


Transitional cell carcinoma is the most common tumor of the lower urinary system (bladder and urethra) in the dog.

  • Locally invasive and likely to metastasize to another area
  • Bloody urine can be seen with tumors of the bladder
  • Straining or urethral obstruction can be seen with tumors below the bladder


Most mast cell tumors are found on the skin and may be detected by a sudden swelling or growth.

  • Fairly simple to diagnose with a needle aspirate
  • Boxers and Bulldogs are more frequently diagnosed


Osteosarcoma is the most common type of primary bone tumor in the dog.

  • Frequently affects the long bones (But can be found in any bone)
  • Associated with the giant breeds
  • 7 – 10 year old dogs
  • Very aggressive and rapidly growing tumor


Mammary Carcinoma - Tumors of the mammary glands are the most common tumor seen in unspayed female dogs.

  • Most commonly found in unspayed cats and dogs
  • 40 – 50% of these tumors are malignant (they have spread to other locations—most often the lungs or lymph nodes)
  • Open wounds or ulcerations on the mammary mass can be seen
  • Treatment may include surgical removal of the entire mammary chain and mass
  • Prevent by spaying your pets!


Basal cell tumor is the one of the most common skin cancers in animals.

  • Hairless, raised mass in the skin that may be located on the neck, head, and/or shoulders
  • Older dogs, especially poodles and cocker spaniels
  • Can be benign or malignant
  • Growth away from the original site is rare
  • Less than 10% of these tumors are malignant