How do you differentiate between Hodgkin’s disease and lymphoma (i.e. how will the doctor determine whether a person has one or the other)? How do symptoms differ? Are the treatments vastly different?
Lymphomas are tumors arising within or made up of cells from the lymphatic system. The lymphatic system consists of the lymph nodes, the fine lymphatic channels that drain all tissues into the lymph nodes, and the spleen. Since the lymph nodes drain all our tissues, cancers, such as breast cancer, will commonly spread to the local lymph nodes. Such cancers are not lymphomas, which are caused by the types of cells that originate in the lymph nodes themselves.
The lymphomas are broadly divided into two types; Hodgkin’s disease and non-Hodgkin’s lymphomas (NHLs). NHLs are about five times as common as Hodgkin’s disease, and the number of new cases is increasing, at least in part due to the HIV epidemic. Several types of NHLs are seen predominately in people with AIDS or other immune suppression: the NHL tends to rise in the brain, bone marrow, or gastrointestinal tract. These sites are uncommon origins for NHLs in people with normal immune systems.
NHLs are most likely caused by viruses. Studies in animals have shown that many of their NHLs are caused by viruses; in humans at least three different NHLs have a viral origin: African Burkitt’s lymphoma; the high-grade lymphoma seen in people with AIDS; and adult T-cell lymphoma, which is associated with HTLV-1 (human T-cell leukemia virus 1). HTLV-1 is found mostly in the Caribbean and Japan.
In any person suspected of having a lymphoma, it is crucial to distinguish between Hodgkin’s disease and NHL and to determine which type of Hodgkin’s or NHL is present, since the course of the disease and the treatment differs a great deal. A biopsy of the enlarged lymph node or other tissue is an essential first step. Once the type of lymphoma is determined, the stage of the disease, that is the extent of spread of the lymphoma, must be established.
Hodgkin’s disease is a curable malignancy with modern treatments, which utilize radiation therapy, chemotherapy or both. About 75 percent of Hodgkin’s disease patients are cured of their disease. In contrast, only about 30 to 40 percent of patients with NHLs are curable, but this is very dependent on which type of NHL the person has. Radiation is less commonly used in treating NHLs because the tumors tend to be more widespread, in contrast to Hodgkin’s disease which often is diagnosed when only a small group of lymph nodes are involved. The chemotherapy regimens used for NHLs are often different from those used in Hodgkin’s disease.
Both types of lymphoma are usually discovered by noticing enlargment of some lymph nodes. Symptoms are usually not present, although a minority of people with these conditions will have unexplained fever, weight loss, or severe unexplained itching. Hodgkin’s disease is commonly seen first in the lymph nodes of the neck or chest, whereas NHLs more frequently arise in the lymph nodes of the throat — the tonsils and adenoids — and the groin or abdominal nodes. Enlarged lymph nodes in both types of lymphoma are almost always painless, in contrast to the enlarged nodes seen in infections, which are often quite tender.