Lymphoma Lymphoma is a cancerous tumor originating in the lymph system. The lymph system is a connecting network of glands and vessels which produce and circulate lymph through the body. Lymph is a colorless, watery fluid that contains white blood cells called lymphocytes. Along the vessels are organs called nodes. Lymph nodes are found in the neck, under the arms, in the groin and abdomen.
Lymph nodes make and store infection fighting cells.
When lymphoma occurs, cells in the lymphatic system grow abnormally. They divide to rapidly and grow without order or control. The cells are immature and do not die like a normal cell. They continue to divide as immature cells that cannot do their jobs well. Too much tissue is formed and tumors begin to grow.