Along the network of vessels are groups of small organs called lymph nodes. Clusters of lymph nodes are found in the underarm, pelvis, neck, and abdomen. The lymph nodes make and store infection-fighting cells. Because lymph tissue is found in many parts of the body, non-Hodgkin's lymphoma can start in almost any part of the body. There are many types of non-Hodgkin's lymphomas.
Some types spread more quickly than others.
The type is determined by how the cancer cells look under a microscope. This determination is called the histology. If these symptoms are present, a doctor will carefully check for swelling or lumps in the neck, underarms, and groin. If the lymph nodes don't feel normal, a doctor may need to surgically remove a small piece of tissue and look at it under a microscope to see if there are any cancer cells. This procedure is called a biopsy.