Mediastinal Lymphoma in Dogs

Mediastinal lymphoma is a malignant form of cancer. Some breeds of dogs may be at increased risk of lymphoma. These breeds include Rottweilers, Scottish terriers, golden retrievers, Basset hounds, and German shepherds.

  1. Identification

    • Mediastinal lymphoma, also referred to as thymic lymphoma, occurs in the front of the heart in the thymus (the chest). This area is also known as the mediastinum. Other types of lymphoma that may affect dogs are multicentric lymphoma (occurs in the lymph nodes), gastrointestinal (occurs in the stomach, intestines, liver, lymph nodes and abdomen) and cutaneous lymphoma (occurs in the skin). The most common form of lymphoma in dogs is multicentric lymphoma, which accounts for 80 percent of all dogs with lymphoma.

    Symptoms

    • The symptoms associated with mediastinal lymphoma in dogs depends on the location of the tumor. Dogs with mediastinal lymphoma typically have difficulty breathing and increased thirst. Other symptoms that may occur with lymphoma are enlargement of lymph nodes, vomiting, diarrhea, loss of appetite, weight loss, lethargy, difficulty breathing, increased thirst and frequent urination.

    Causes

    • According to petplace.com, mediastinal lymphoma in dogs may be attributed to dogs that have a family history of lymphoma and is often breed specific. Veterinarians believe that the development of lymphoma may be related to exposure to the herbicide 2, 3-D.

    Diagnosis

    • The diagnosis of mediastinal lymphoma may be made upon examination of the lymph nodes. A needle aspiration of cells from an enlarged lymph node may be performed and examined under a microscope. Other tests such as endoscopy, CBC (complete blood count), abdominal ultrasound, X-rays or an MRI may be performed in order to determine if the cancer has spread to other areas of the dog's body.

    Treatment

    • The treatment for lymphoma in dogs may be surgery if possible to remove the tumor, followed by radiation or chemotherapy. According to petplace.com, the most commonly recommended treatment for lymphoma is chemotherapy. The objective with this treatment is to achieve remission of symptoms rather than a full cure. A dog is thought to be in remission if clinical evidence of lymphoma disappears after treatment.