Dog Cancer Symptoms

"Dogcancer symptoms tend to be common to many types of canine diseases.Cancer is an emerging health issue and is of great importance since itis life threatening in most cases.Some dogs are genetically predisposed to it while others may acquire itfrom pathogens (disease causing), toxins, drugs and as a complicationof some commonhealth problems. Canine cancer symptoms are highly non specific andresemble many common health problems in the initial stages of thedisease. Unfortunately, once the cancer is identified as the cause itis often incurable, such it will be in a more advanced stage. Bothbenign (slow spreading) and malignant (fast spreading) forms of dogcancerscan be result in severe symptoms, benign tumors are less dangerous.Clinical studies show that dog cancer symptoms are exhibited in twodifferent phases, initially mild, while recurring and severe inadvanced stages. Dog cancer symptoms are only helpful in suspectingthat cancer is the cause and not that helpful. Onlydetailed laboratory and pathological sampling can confirm the presenceand extent of the disease. Alongwith specific treatment through surgery, chemotherapy and theapplicationof radiation, symptomatic therapy can help in improving the quality ofthe affecteddogs. Incurable dogs are usually kept on life long symptomatictreatment plans only."

General Dog Cancer Symptoms:

Dog cancer symptoms are highly non specific, any dog can acquirecancer, but older dogs and females are more susceptible. Similarly,somebreeds such as boxers, terriers and retrievers etc are potentiallypredisposed to cancer genetically. Dogs with a malignant (fastspreading) form of cancershow more severe and generalized symptoms, while those with benign(slow growing)tumors/cancers usually show no or less symptoms initially, but theseverityincreases gradually.

Generally, a dog with cancer appears dull, non social, anorexic(appetite loss),ataxic (uncoordinated muscle movement), intolerant and gradually losesweight. Any of these symptomsusually do not help in making a confirmatory diagnosis, as thesesymptoms may beseen in many other health problems of dogs.Involvement of a specific part, system or organ of the body can help tosome extent to suspect dog cancer as the underlying cause.

The VeterinaryCancer Society publishes a helpful list of common cancersymptoms in small animals.  These include:

   1.  Abnormalswellings that persist or continue to grow
   2. Sores that do not heal
   3. Weight loss
   4. Loss of appetite
   5. Bleeding or discharge from any body opening
   6. Offensive odor
   7. Difficulty eating or swallowing
   8. Hesitation to exercise or loss of stamina
   9. Persistent lameness or stiffness
  10. Difficulty breathing, urinating, or defecating

Systemic Dog Cancer Symptoms:

Dog cancer can appear at any part of the body, andcan be caused by any number of factorsas pathogens such as viruses, high doses or prolonged use of somedrugs,extreme defects in physiology etc. Age is a significant factor inthe development of dog cancer.

Different organs/systems such as the bladder,liver, pancreas, intestines, lungs,spleen, mammary glands, testes or bone marrow can be the site of a dogcancer. Similarly the lymphatic system, musco-skeletal system,circulatory systemand urinary system are the most commonly affected parts of a dog'sbody almost all typesof malignant forms of cancer. Lymphomas (lymphatic tissue),hemangiosarcomas (bleeding in the heart, liver, spleen and skin),osteosarcomas (bone) are some examples of such deadly dog cancers.

Specific dog cancer symptoms that are related to affected organs orsystems aresometimes helpful in making a diagnosis. Difficulty in urination,abdominalpain, bleeding through open cavities (ears, nose, anus etc), unusualgrowths and lumps on the dog's body which grow larger with time,recurringvomiting, incurable diarrhea etc. are somewhat specific signs for dogcancer.

One most common finding which lead to the suspicion of a dog cancer isthe recurrence andincurability of symptoms, even if symptomatic treatment has beenapplied. Ulcers are the best example, which are related to abdominalpain.Ulcers that recur even after symptomatic treatment, can cause thepassing of bloodinto the feces and may develop into an incurable malignant form of dogcancer.

Dog Cancer Symptoms and Diagnosis:

Canine cancers which occur on the surface of theskin, such as dog skin lumps or lesions can bediagnosed symptomatically, but confirmation usually requires a biopsy(tissue sample lab test) anddetailed studies. Dog cancers which occur in deeper tissues and systemscan be suspected based on a dog's history and clinical symptoms, butcan never beconfirmed this way.

Different procedures involving pathologicalsampling, biopsy,biochemical profiling and radiography can only confirm the type,severityand possible outcome of dog cancer.

Treatment of Dog Cancer Symptoms:

After confirmation of the disease, a veterinarianusually decides the prognosis orpossible outcome of condition. Treatment of dog cancer is purelydependent upon the prognosis.

Specific treatment options for dog cancer aresurgical excision of thetumors, use of chemotherapy (anti – cancerous drugs) or application ofradio waves to eliminate it.

Along with specific treatment and to counter theside effects of treatment, symptomaticand supportive treatment options are highly recommended. These mayinclude pain management, approaches to resolve weight loss and staminaand supportivetherapies with balanced diets and supplements.

Some incurable dog cancer cases are kept on asymptomatic treatmentapproach only. Symptoms such as vomiting, pain, anorexia, andresolution of bodyconditions are usually managed by administering relevant drugs.Similarly, regular detoxification and maintenance of body conditions orcellular health is required, which can be done with specific drugs onprescription or through herbal/homeopathic medicines such as an overthe counter natural anti-oxidant. These optionsshould be decided by a veterinarian, as different dogs responddifferently.


Morrison, Wallace B. “Cancer in Dogs and Cats” –1998

Merck Veterinary Manual (Merck & Co. 2008)

Washington State University College ofVeterinary Medicine

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