Canine Health Menu

Canine Liver Cancer

Issue Description
Primary liver cancer is rare, comprising less than two percent of all cancer seen in these species. When it does occur, the most common primary liver tumors seen in dogs are hepatocellular carcinomas, which are malignant tumors that arise from the liver cells, and hepatocellular adenomas or hepatomas, which are benign tumors that arise from the liver cells.
Other Names
Liver Cancer, Hepatic Neoplasia, Hepatocellular Carcinoma, HCC, Malignant Hepatoma

Primary liver cancer is the result of a primary liver tumor (one that originates in the liver). The most common primary liver tumor is the hepatocellular carcinoma which usually does not spread to other parts of the body. Instead, the tumor invades into the liver tissue.

Primary liver cancer is less common than metastatic liver cancer in dogs. Primary liver cancer occurs more frequently in older dogs (10 years of age or older). There is a slightly increased risk of primary liver tumors in male dogs. Although rather rare, primary liver cancer in dogs can also metastasize to other parts of the body.

Metastatic, or secondary, liver cancer is one that has spread to the liver from other organs. Metastatic liver tumors are generally multiple nodules.

The liver is the largest organ in the dog's body, and it is involved in a large number of bodily functions and processes. In particular, the liver is one of the main organs responsible for detoxifying many toxic substances circulating in the body. It is understandable, therefore, that the liver is one of the primary targets of almost all metastatic cancers. Cancer that metastasizes tends to travel to the liver through the blood stream or the lymphatic system, and the fact that the liver is supplied blood through two blood vessels instead of one makes it all the more vulnerable. The cause of primary liver cancer may be related to environmental factors, such as exposure to cancer-causing chemicals (carcinogens). Examples of possible carcinogens include chemicals in some commercial pet food (food additives, artificial coloring and flavors), certain pesticides, dyes, etc.

Liver cancer in dogs can happen at any age. In younger dogs and puppies there is a greater possibility of liver shunt, toxicity and viral diseases. In older dogs, inflammation and cancer is more probable than other conditions. Even though liver cancer does not show specific symptoms, severity of the symptoms below demands additional investigation to eliminate prevalence of malignancy:

  • The most common symptom loss of appetite. Anorexia frequently contributes to a weight loss and improper metabolism of fats, carbohydrates and proteins further complicates an already complex situation. Poor appetite also causes anemia. Anemia can also be caused by disease in liver cells.
  • Increase in urination and excessive thirst is commonly associated with other diseases like diabetes and kidney diseases but is one of the important indications of prevalence of liver cancer in dogs.
  • Light colored feces can be an indication of liver cancer as a tumor prevents the secretion of normal bilary pigments into the intestines.
  • Clotting of the blood is one of the important functions of the liver. Liver cancer in dogs can suppress this function and cause bleeding problems.
  • If the tumor is large enough, it can be found by probing the region from outside. A distended stomach and abdominal pain can also suggest liver cancer.
  • In serious conditions, liver cancer leads to jaundice. If the mucous membranes are yellowish or the dog is passing orange colored urine, it is a sure signal of jaundice and should be taken to the vets for an examination.

  • Diagnosis
    While sophisticated diagnostics, including body scans, can help to identify potential tumours, a sample of tissue from the suspected area is necessary for an accurate diagnosis of cancer. Small tumours may simply be removed, but for larger ones, your vet may either take a small piece of suspect tissue (a biopsy), or use a needle and syringe to withdraw a sample of cells to be analysed. Cancers generally occur later in life, but can also affect younger individuals. Early diagnosis is vital, and dogs over seven years old should have yearly preventative veterinary examinations.

    Treatment for cancer is pretty general for all forms. The vet will look at the size of the tumor and decide if surgery is an option. You may not want an invasive procedure as well. Keep in mind that if surgery is an option it usually is the best thing to do to help your dog feel better. If the mass is too large surgery will not be an option and the vet will recommend medication, radiation, and/ or chemotherapy. The medications and therapy are to help reduce the cancer cells as well as prevent more cells from forming. It is important to realize that radiation and chemotherapy can last for several treatments before you will see results. In some cases the cancer may be too far along to do much good. It is always best to help make the dog as comfortable as possible.

    It is difficult to detect liver cancer in its early stages, and prognosis of the advanced stage is extremely poor.

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