A pet’s cancer diagnosis is never easy, but advancements in veterinary medicine give pets a much better chance of successful treatment and recovery. Early diagnosis and treatment also greatly improve a pet’s prognosis. Our team at Sixes Animal Hospital at Bridgemill shares some of the most common pet cancers and their signs, so you can learn potential cancer indicators in your pet. 

Lymphoma signs in cats and dogs

Lymphoma is one of the most common cancer forms for cats and dogs. Canine lymphoma typically involves one or more external lymph nodes—the first sign pet owners notice is often enlarged lymph nodes under the jaw, behind the knee, or in front of the shoulders. In cats, gastrointestinal tract lymphoma is the most common form, with cats with feline leukemia (FeLV) or the feline immunodeficiency virus (FIV) at higher risk. Lymphoma signs are similar in cats and dogs and may include:

  • Weight loss
  • Vomiting
  • Diarrhea

Mast cell tumor signs in dogs

Mast cell tumors, which are the most common skin tumor found in dogs, generally form as bumps on or right under the skin, but also can occur in the spleen, liver, intestine, and bone marrow. This cancer can be cured if the tumor is detected early and fully removed. While all dogs can develop mast cell tumors, some breeds are at a higher risk, including boxers, bull terriers, Boston terriers, Labrador retrievers, golden retrievers, and schnauzers. Mast cell tumor signs include:

  • Raised lumps or bumps — Lumps and bumps will appear on or close under the skin, and may be red, ulcerated, or swollen. Some will exist for months with little growth, while others appear suddenly and grow quickly.
  • Vomiting, loss of appetite, lethargy, and melena — These signs can indicate that the dog has internal bleeding because of a tumor in the upper gastrointestinal tract, the esophagus, stomach, or small intestine. 

Melanoma signs in dogs

Melanoma tumors are also found on the dog’s skin. Many melanomas are benign and easily treated, but if malignant, they spread quickly. The malignant melanoma signs vary, depending on the tumor location, most commonly the mouth, skin, and toes. Signs in these locations include:

  • Oral melanoma signs — A pet with an oral melanoma may have a dark lump or lesion on their mouth, tongue, lips, or gums, and will find eating difficult. They also may have facial swelling, bloody drool, and bad breath.
  • Skin melanoma signs — Melanoma on the skin may appear as a rash or small blister-like lesions on the feet, belly, or face, or may develop anywhere else as a large lump that is darker than the surrounding skin. A wound that does not heal may be melanoma.
  • Melanoma signs on the toes — In this location, melanoma can cause foot swelling and discolored, loose toenails.

Osteosarcoma signs in dogs

Osteosarcoma is a painful form of bone cancer that most commonly affects the limbs of large- and giant-breed dogs, but can also develop in the ribs, spine, and pelvis. As osteosarcoma progresses, your pet will become more painful as their bone is weakened and destroyed, leading to a fracture. Affected dogs may display these signs:

  • Limping
  • Reluctance to jump
  • Leg swelling
  • Muscle atrophy

Mammary cancer signs in cats

Mammary tumors are, sadly, 85% malignant. They occur most commonly in female cats, who should be spayed before their first heat cycle to significantly reduce their mammary cancer risk. 

If your pet does have a mammary tumor, your veterinarian will likely recommend surgery, followed by chemotherapy. The most common mammary tumor signs include: 

  • Lumps or swelling — Lumps or swelling of the mammary tissue and nipples along the belly can indicate mammary cancer. 
  • Sores — Mammary tumors may cause ulcerations and nipple discharge.

Squamous cell carcinoma signs in cats

Squamous cell carcinoma accounts for a high percentage of all skin tumors in cats, and  frequently affects light-colored and white cats. Sun exposure increases risk of this cancer. Feline squamous cell tumors commonly appear on the hairless areas of the nose, eyelids, and ears, and signs include a white, raised bump on the skin, or a crusty or bleeding sore on the skin that will not heal.

Cancer can affect cats and dogs in many forms and can progress rapidly, but the sooner your pet is diagnosed, the better their prognosis. If you suspect that your pet has signs that may indicate cancer, schedule an appointment with our Sixes Animal Hospital at Bridgemill team.