Treating Lymphoma in Dogs with Radiation Therapy

Lymphoma in dogs occurs in canines of any age group or breed. Lymphoma is the term used to describe cancers of the lymph tissues or lymphoid system. Since lymph tissues are present in all parts of the dog’s body, the location of cancer determines the type of lymphoma the pet suffers from.

Types of Canine Lymphoma Include

  • Multicentric lymphoma is lymphoma that affects the lymph nodes. It’s the most common type of canine lymphoma and may cause internal organ failure.
  • Gastrointestinal lymphoma affects the digestive tract, or intestines. It causes severe digestive problems and can cause a build-up of waste in the body.
  • Mediastinal lymphoma involves the presence of tumors in the dog’s respiratory system such as the lungs and thorax. It causes labored breathing, pain and, in some cases, suffocation.
  • Extra nodal lymphoma manifests itself in tumors that affect the pets, eyes, skin, liver, bone or mouth.

Treatment of Canine Lymphoma

The treatment for most dogs involves chemotherapy with the use of drugs such as prednisone, doxorubicin, cyclophosphamide and vincristine. The medication can be administered either orally or through intravenous injections. The protocol for chemotherapy varies according to the severity and type of lymphoma present. Chemotherapy helps to reduce metastasis and prolongs the pet’s life by one year. Another procedure used to treat canine lymphoma is combination therapy. This involves the use of chemotherapy and radiation therapy to kill cancer cells. Although surgery is not performed on all pets, it may be performed on few pets, to remove malignant tumors that are easily accessible. Surgery is also conducted in combination with radiation therapy.

Radiation Therapy

Radiation therapy uses gamma rays or photons to shrink tumors that can’t be surgically removed. It’s often used post-surgery to kill cancer cells that are left in the body. Pets may also be treated with half-body radiation in order to prevent damage to the bone marrow. Pet owners should discuss treatment options with the vet to determine if radiation therapy is best for the dog. Pets that have cancer that’s spread to various parts of the body may not benefit from radiation therapy. Radiation therapy also involves the pet owner’s commitment to both time and money as most pets require treatment with radiation therapy several times a week for a specific duration of time.

Other tests

Radiation therapy helps reduce pain and discomfort and is also used to treat osteosarcoma or bone cancer in dogs. In order to perform radiation therapy the vet will conduct MRI’s, scans and x-rays to determine the location of the tumor in the body. The dog will also be anesthetized before radiation therapy commences. The radiation machine is then focused on the marked location to allow the beams to penetrate the nucleus of the tumor.


Treatments such as brachytherapy use radiation implants, inserted surgically after the removal of tumors, to treat cancer cells. The implants also known as after-loading tubes contain radiation that’s emitted in small doses to kill any remaining cancer cells or malignant tissues.

Dogs respond well to chemotherapy and most pets have an increased life expectancy with medication and proper home care.