Most Common Cancers and Signs in Pets
What are the most frequent cancer cases we see and treat at Paragon?
Lymphoma (dogs & cats) and Mast Cell Tumour (dogs):
What is Lymphoma?
It is a cancer of the lymphocytes, a type of white blood cell associated with the immune system, and lymphoid tissues. Lymphoid tissue is normally present in many places in the body including lymph nodes, spleen, liver, gastrointestinal tract and bone marrow. The exact origin of lymphoma in dogs is unknown. We do know that lymphoma can affect dogs at any age, but it is most often seen in dogs between the ages of 5 and 9. It is equally distributed between the sexes and it is one of the most common cancers of the dog. A genetic predisposition to lymphoma is seen in some breeds – most commonly the Golden Retriever, Flat Coat Retriever, Boxer, and Scottish terrier. The feline leukaemia virus (FeLV) has been shown to cause lymphoma in cats. We believe that the feline leukaemia virus is responsible for many of the cases of lymphoma. Cats with the feline immunodeficiency virus (FIV) are also at higher risk of developing lymphoma. Cats of any age, breed and sex can be affected. We typically see lymphoma in younger cats that are infected with the feline leukaemia virus, and in older cats that are not infected with the virus.
What is a Mast cell Tumour (MCT)?
Mast cell tumours are common skin tumours in dogs. They account for 20-30% of all skin tumours in dogs. They are a cancer of mast cells, which are cells important in the immune response. They often occur in dogs that have a history of allergic skin disease. About 50% occur along the trunk and perineum, 40% along the extremities and 10% along the head and neck. These tumours include both benign (relatively harmless) and highly malignant (more dangerous and spreading) types. Some are multiple. Recurrence of the tumour and spread to other parts of the body (metastasis) is possible with some types.
What are the common signs to look out for in your pet?
Most pets with cancer are described as “normal” by their owners, and may show no clinical signs at all, unless some organ or system is compromised. This is a typically more of a disease and not necessarily a sickness. So, most cancer patients are not necessarily sick or even painful, until more advanced stages of the disease are reached. This is why the signs mentioned above are important to look out for, for an earlier diagnosis.
Lymphoma – Any persistent and progressively enlarging lymph nodes and/or any persistent & progressive abnormal clinical signs, may be related to lymphoma.
MCT – Any lumps or bumps in the skin, under the skin or on the skin. They can be hard, soft, red or white and are usually persistent and progressive. They can occur as a solitary lesion or be multiple. They can be haired, ulcerated, pedunculated etc and because of their different appearances are often called the great imitator.
In most cases dogs have a history of the mass being present and changing in size over time.
When should your Vet refer your pet?
It would be optimal for patients to be referred, at least for a consultation, possibly even a remote one, once there is even a suspicion of cancer. That way the clinical oncologist would be able to guide the owner and the primary vet as to what diagnostics and treatment would be most appropriate and cost effective, for that particular patient and owner.