Lymphoma is a cancer which affects lymph nodes and spleen. It start when cells present in the lymph system changes and develop uncontrollably that might create a tumor. The lymph system is generally fabricated of thin tubes that broaden to all parts of the body and having functionality to fight against infection and disease. The spleen generally contains lymphocytes and also helps in fighting against infection. Your doctor might suspect lymphoma based on the symptoms and diagnostics like an excisional biopsy, a bone marrow, and blood tests.