Features of Benign and Malignant Tumors in Dogs

Tumors in dogs are caused when an abnormal quantity of cells are produced by the body. Normally, after a dog has attained maturity, the body stops producing new cells except to replace dead cells. Sometimes, due to damaged DNA or external factors, this balance between the growth and death of cells is disrupted. The cells grow rapidly and the immune system fails to stop this growth. A mass of cells is formed and this mass is called a tumor. These cells aren’t required by the body and perform no specific function.

Diagnosis of Tumors

Tumors are classified as benign or malignant tumors. If you find a lump or tumor on your dog’s body, it’s advisable to seek vet care immediately. Definite diagnosis is obtained through a diagnostic test called a biopsy. This is a microscopic examination of a part of the tumor which helps determine whether the tumor cells resemble those of the surrounding organs. If they do, the tumor is a benign one and if the tumor cells don’t resemble the normal cells of the organ, the tumor is a malignant tumor.

Characteristics of Benign Tumors:

  • Benign tumors aren’t harmful. They consist of cells which resemble the normal cells of the organ in which they are found.
  • They grow in one location.
  • They’re encapsulated in fibrous tissue and are thus easy to remove.
  • In some rare cases, benign tumors can become malignant.
  • Though benign tumors are harmless, the location of the tumor sometimes causes inconvenience to the dog and has to be surgically removed.
  • Rapidly growing benign tumors can also exert pressure on the surrounding organs and affect their functioning. This can be harmful to the health of the dog.

Characteristics of Malignant Tumors:

  • Malignant tumors are harmful. They consist of cells which don’t resemble the normal cells of the organ associated with the tumor.
  • They can metastasize from one organ to another through the blood stream or the lymphatic system and hence spread to various parts of the body.
  • In the initial stages, malignant tumors are encapsulated in fibrous tissue but in later stages, they don’t stay restricted to the organ from which they develop and don’t remain encapsulated in fibrous tissue.
  • Due to metastasis, it’s difficult to ensure that all cancerous cells are removed during surgical extraction.
  • Often it’s impossible to remove them surgically as they have metastasized to vital organs and it would endanger life to do so.
  • Carcinomas are malignant tumors found in the central nervous system, eyes, lungs, liver, skin and pancreas.
  • Sarcomas are those found in the blood vessels, the musculoskeletal system, and the urinary tract.

Treatment usually comprises of surgery, radiation and chemotherapy. Neutered dogs are 4 times at risk of developing prostate cancer than other pets. Canine benign and malignant tumors can both be potentially deadly and it’s prudent to be aware of any abnormal growth on your pet’s body. Pet owners should also work with the vet to determine treatment options suited to individual pets to help them have a better quality of life.