Lymphoma (Feline)

by Petside Team

Share

Lymphoma is one of the most common forms of cancer diagnosed in cats. Lymphoma is a cancer of lymphocytes, a type of white blood cell found throughout the body. Diagnosis and treatment require veterinary care.

Common name: Lymphoma
Scientific name: Lymphoma, Malignant lymphoma, Lymphosarcoma (old term, not accurate description).

Diagnosis

Signalment
Lymphoma can affect cats of any age, but it is most common in cats over 9 years of age. Cats infected with feline leukemia virus and/or feline immunodeficiency virus are more likely to develop lymphoma.

Cats that are infected with feline leukemia virus tend to develop lymphoma at a much younger age, between 4 and 6 years of age or younger. Siamese cats may be more prone to develop lymphoma than other breeds.

Incidence/prevalence
Lymphoma has long been considered the most common cancer affecting cats. The prevalence may reach 200 per 100,000 cats, or 0.2 percent.

Geographic distribution
This cancer is seen in cats throughout the world but is most prevalent in areas with a large number of cats with feline leukemia virus and/or feline immunodeficiency virus.

Clinical signs (primary, most to least frequent, scientific term, synonyms)
Mediastinal lymphoma (thorax or chest), Dyspnea (difficulty breathing), Alimentary lymphoma (gastrointestinal tract), Weight loss, Vomiting, Diarrhea, Anorexia (decreased appetite), Multicentric lymphoma (multiple organ systems), Anemia, Jaundice.

Clinical signs (secondary, most to least frequent, scientific term, synonyms)
Nasal lymphoma, Sneezing, Epistaxis (nosebleeds), Nasal discharge, Dyspnea (difficulty breathing), Facial deformity, Ocular lymphoma, Blindness, Abnormal-appearing eye, Cutaneous lymphoma, Alopecia (hair loss), Inflamed skin (red, flaking, crusting), Spinal or central nervous system lymphoma, Behavioral abnormalities, Ataxia (difficulty walking), Renal lymphoma, Polydipsia (excess water drinking), Polyuria (excess urine production), Vomiting, Anorexia (decreased food consumption), Weight loss.

Cause (scientific, common term)
The cause of lymphoma is unknown. Infection with feline leukemia virus and/or feline immunodeficiency virus predisposes cats to the development of lymphoma.

Organ systems affected (most to least affected)
Gastrointestinal tract, Thoracic cavity, Liver, Spleen, Lymph nodes, Spinal cord/brain, Kidneys, Nasal cavity, Skin, Eye.

Diagnostic tests
Cytology on an aspirate of the affected organ, Biopsy of the affected organ, Radiograph (X-ray), Ultrasound.

Differential Diagnosis Äî depends on the location of the lymphoma: Inflammatory bowel disease, Heart disease, Feline infectious peritonitis, Diaphragmatic hernia, Liver disease, Rhinitis, Allergic dermatitis, Dermatomycosis (fungal infection of skin), Renal failure, Cancer.

Overview

Lymphoma is one of the most common forms of cancer diagnosed in cats. Lymphoma is a cancer of lymphocytes (a type of white blood cell) and can affect virtually any area of the body. The cause is unknown, but infection with feline leukemia virus (FeLV) and/or feline immunodeficiency virus (FIV) increases the likelihood a cat will develop lymphoma.

While lymphoma has been diagnosed in cats as young as 4 months of age, it is more common in cats 9 years of age or older. Cats infected with FeLV tend to develop lymphoma between 4 and 6 years of age. Siamese cats may be predisposed to the development of lymphoma. Clinical signs seen depend on the area of the body affected by the cancer.

The most commonly affected site is the stomach and/or intestines (alimentary lymphoma), with clinical signs of weight loss, vomiting, diarrhea and anorexia. The next most common is the chest cavity (mediastinal lymphoma), with clinical signs including rapid respiratory rate and difficulty breathing. Liver, spleen and lymph nodes (multicentric lymphoma) may be affected, with clinical signs including weight loss, anorexia and possibly jaundice. The nose can be affected (nasal lymphoma), with clinical signs of sneezing, nosebleeds, nasal discharge (often one-sided) and in some cases facial deformity. Lymphoma of the brain/spine (central nervous system lymphoma) can develop, with clinical signs including behavior change and difficulty walking. Kidney involvement (renal lymphoma) may occur, manifesting as weight loss, increased water intake and urine output, and in some cases vomiting. The skin may be affected (cutaneous lymphoma), presenting with alopecia, crusting, flaking and red discoloration of the skin. Anemia is common in cats with lymphoma, regardless of the location of the cancer.

Treatment

Home Care
Treatment for lymphoma requires veterinary care. Home nursing is important once treatment is initiated. Since infection with FeLV and/or FIV predisposes cats to the development of lymphoma, it is best to keep cats indoors to reduce their risk of exposure to these viruses. FeLV and FIV tests should be done on all suspect cases. Cats with positive test results should be housed separately from cats with negative results.

Professional Care
The diagnosis of lymphoma is made based on the observation of malignant lymphocytes under a microscope. A veterinarian may use X-rays or an ultrasound to determine which organs are likely to contain the malignant lymphocytes. An aspirate or biopsy of the affected organs can confirm the diagnosis. Once the diagnosis is made, the veterinarian will develop a treatment plan tailored to the specific patient based on the area of the body affected by the lymphoma.

Chemotherapy is the most effective means of treating most cases of lymphoma. Depending on the affected area, specific care such as radiation for nasal lymphoma may be indicated. There are a variety of different chemotherapy and radiation treatment protocols a veterinarian may recommend based on the individual circumstance. Most cats handle chemotherapy and radiation treatments remarkably well.

Action
Veterinary care is required to diagnose and treat feline lymphoma. Depending on the specific case, a veterinary oncologist may be consulted.

Outcome
While feline lymphoma is rarely cured, current treatment protocols can extend the length and quality of life for many cats with this disease.

References/Additional Readings

Vail, D.M. Feline Lymphoma and Leukemia. In: Withrow S.J., Vail, D.M. Withrow &
MacEwen's Small Animal Clinical Oncology, 4th ed. St. Louis: Saunders Elsevier, 2007; 733-756.

Moore, A.S., Ogilvie, G.K. Lymphoma. In: Ogilvie, G.K, Moore, A.S. Feline Oncology: A Comprehensive Guide to Compassionate Care. Trenton: Veterinary Learning Systems. 2001; 191-219.

Author
Josephine McKnight, DVM
ACVIM (Oncology)

Editor

Steven Hansen, DVM, MS, MBA
DABVT, DABT