Thymoma in Rabbits

In rabbits and other mammals, the thymus is a small organ in the chest that produces immune systems cells. A type of cancer, thymoma occurs when cells on this organ begin to grow uncontrollably, forming tumors.

  1. Prevalence

    • Thymoma occurs in approximately 8 percent of all rabbits, reports Dr. James K Morrisey of the Cornell University College of Veterinary Medicine.

    Symptoms

    • Thymoma in a rabbit may cause shortness of breath, causing the animal to pant or breathe with its mouth open. The rabbit's eyes may bulge or a swelling may develop around its head, neck or legs.

    Diagnosis

    • To locate the tumor, veterinarians usually rely on diagnostic imaging like magnetic resonance imaging (MRI) or computerized tomography (CT scan). The vet may take a sample of fluid from the tumor using a needle or remove a small part of the growth to determine that the tumor is cancerous.

    Treatment

    • Approximately 50 percent of rabbits survive surgical removal of the thymoma, and those that do often recover fully from the disease, reports Morrisey. Approximately 80 percent of rabbits survive radiation for thymoma, but there is a higher risk that the disease will return with this method of treatment.

    Considerations

    • Both surgery and radiation for thymoma in rabbits are expensive treatments, reports Morissey. Because of this, pet owners may ultimately opt for euthanize the affected animals.