According to Mayo Clinic and the American Society of Hematology, it is unknown what causes lymphoma. Factors that increase a person's risk of developing lymphoma include being an older Caucasian male, having an autoimmune disease, eating a diet high in meat and fat and exposure to certain pesticides. The two types of lymphoma, non-Hodgkin's lymphoma and Hodgkin's lymphoma, occur when mutated lymphocytes spread and concentrate in the lymph nodes.
The lymphatic system, which is part of the immune system, aids in the movement of fluids throughout the body and helps fight infections. Lymphocytes such as B cells and T cells make up the lymphoid tissue. According to the American Cancer Society, both Hodgkin's lymphoma and non-Hodgkin's lymphoma can start in the lymph nodes, but they spread and react to treatment differently requiring doctors to diagnose lymphoma correctly.
Mayo Clinic notes that a lymphoma cancer patient's doctor takes into account the patient's age, overall health and type and stage of lymphoma to determine the necessary treatments needed. The treatments for lymphoma include chemotherapy in combination with radiation, biological therapy, stem cell transplant and medications such as Rituxan, Zevalin and Bexxar. Non-Hodgkin's lymphoma patients may not need treatment immediately if their lymphoma grows slowly.