Lymphoma (or LSA), a tumor caused by a cancerous proliferation of lymphocytes (cells that normally function in the immune system), is one of the most common tumors seen in dogs.
It affects dogs of any breed and age, although most dogs will be middle-aged or older at the time of diagnosis; Golden retrievers are considered a breed at increased risk of developing LSA. The cause of LSA in dogs, as is true for most canine tumors, is not known.
Please Read More About Canine Lymphoma by the WSU Vet School
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