Welcome to our series on Common Ferret Illnesses, and specifically our deep-dive into ferret lymphoma. In this article, you will learn what causes it, the most common symptoms, and which ferrets are most at risk. What is Ferret Lymphoma? Lymphoma is cancer of the lymphatic system. These organs are used to fight diseases, so that means if your ferret has lymphoma, they will have a hard time fighting illness. Some experts believe lymphoma may be caused by a virus and therefore able to be spread between ferrets. Symptoms: LethargyDiarrheaWeight lossDifficulty breathingPoor appetiteEnlarged lymph nodes Most at Risk: There are two types of lymphoma. One is called juvenile lymphosarcoma which targets ferrets under 14 months. The other type is called classic lymphosarcoma, which is typically found in middle aged and older ferrets. How Do You Treat Ferret Lymphoma? Sadly, with juvenile lymphosarcoma, ferrets can die instantly. With older ferrets, your ferret will check for enlarged lymph nodes and confirm their diagnosis with a biopsy. Lymphoma can be treated with chemotherapy. Steroids are also sometimes used as a temporary treatment.