Feline
Lymphoma is the most common type of cancer that occurs in cats and it usually occurs in the blood and immune systems. 
Cancerous growths or tumors may occur in the liver, spleen, lymph nodes, intestines and bone marrow. It is most common in cats that have been infected with feline leukemia virus (FeLV). The lymphoma spreads throughout the body and the cancer will spread into organs until they eventually fail causing death.
Research and statistics have show that cats actually have a higher rate of lymphoma than dogs or people. As with humans it is treated with chemotherapy depending on the location, and this can actually help to increase life span. Feline lymphoma accounts for one third of the malignancies found in cats.
Feline Lymphoma is not specific to male or female cats or even to cat breeds. The average age of diagnosis is around 10 years of age and this has improved over the years. These improvements are due to better testing and vaccinations and limited exposure to infected animals. It is still up to the owner to bring their cat to the vet so that they can be properly checked and treated.
This lymphoma can be widespread throughout the body and can affect a variety of organs due to lymphocytes found all over the body. The location of the disease very often affects the type of treatment received and chances of survival.
The symptoms of feline lymphoma can be severe. In addition to swollen lymph nodes, felines will also be very physically ill. They will experience weight loss, coat hair will be rough, they may lose their appetite and may experience both vomiting and diarrhea. Depending on the specific location other symptoms may occur which are more severe.
Feline Lymphoma is diagnosed in a number of different ways. These methods include ultrasounds, x-rays, physical exams, blood tests and biopsies. Chemotherapy is the most common treatment, but surgery or radiation therapies are also possible in some cases depending on the size and location of the tumor.
The success of treatment varies in cats depending on how quickly diagnosis has occurred. A high percentage of cats respond to chemotherapy and will live an average of an additional 6 months, but some others can also go into complete remission and live up to 2 years longer. If not properly treated the life span is greatly shortened living only 4 to 6 weeks after diagnosis. 
A complete cure though has not been found, but proper
treatment can help greatly increase life.
In order to prevent this disease in your cat there are a number of things that you can do. The most important is regular checkups at the vet as they can see problems that the common eye would not see. You can actually provide your cat with nutritional supplements and vitamins, which will also help to keep them healthy. You should also keep your cat active, in good physical shape, and on a balanced diet. This will keep their immune system healthy and active in preventing feline lymphoma.
