Lymphomas

Introduction:

Malignant lymphomas or lymphocytic lymphomas, as they are also called, are the 7th most common cause of death in the USA. The two major types are Hodgkin's disease and non-Hodgkin's lymphoma. About 9,000 new cases of Hodgkin's disease are diagnosed each year in the United States. In 1995 with non-Hodgkin's lymphoma more than 45,000 new cases were found in the US in all age groups.

Lymphomas are more common in whites than in blacks, more common in males than in females. The cause is largely unknown. But we do know some factors that play a role. For instance, there are certain genetic abnormalities (Klinefelter syndrome, hereditary platelet dysfunctions etc.) where an increased incidence of lymphoma is known to occur.

Congenital or acquired immunosuppression is also known to be associated with a high frequency of lymphoma development. Chronic exposure to certain herbicides (phenoxyherbicides) leads to a 2- to 5-fold increase in risk of developing a lymphoma. Ionizing radiation such as in the survivors of the Hiroshima nuclear bomb in Japan or in people with ankylosing spondylitis who in the past were treated for back pain with X-ray irradiation, has proven to cause lymphomas. The likely mechanism here is some form of chromosomal break from the radiation leading to altered cell mechanisms and the development of a new lymphocytic lymphoma cell that multiplies rapidly into a big clone of identical cells, unless stopped by treatment.

Hodgkin's disease is a more uniform lymphoma, which is starting at one anatomic region and has a good prognosis, when detected and treated early. On the other hand the more common non-Hodgkin's lymphoma has many histological subtypes from the more benign low-grade lymphomas to the more aggressive high-grade lymphomas. Overall the cure rates are not as impressive with these as the ones for Hodgkin's disease.

Hodgkin's Disease

Introduction:

This lymphoma originates mostly from a swollen lymph node, but can also originate from the bone marrow. There are two peaks of occurrence, one in the age group between 15 and 43 and another age group above age 60. There are twin studies demonstrating that genetic factors play a role, but other studies also provide evidence for environmental causes. For instance, certain occupations such as woodworkers are at a higher risk or patients with Epstein-Barr or HIV virus infections.

Non-Hodgkin's lymphomas (NHL)

As indicated above there are several disease entities contained in this common, but multifaceted disease. NHL can be brought on by different causes. For instance, human T-cell leukemia-lymphoma virus(HTLV-1) is endemic in southern Japan, South America, the Caribbean and the southeastern USA and is the cause of an acute illness called the adult T-cell leukemia-lymphoma. This is one of the NHLs and it presents with an aggressive type illness with skin involvement, generalized lymph gland swelling, enlargement of spleen and liver and a leukemia, where the leukemia cells are malignant T lymphocytes.

Disclaimer:

This outline is only a teaching aid to patients and should stimulate you to ask the right questions when seeing your doctor. However, the responsibility of treatment stays in the hands of your doctor and you.

References:

1. N Engl J Med 329(14):987-994,1997.

2. The Merck Manual of Diagnosis and Therapy. 17th edition, editors M.Beers and     R.Berkow. Whitehouse Station, N.J., 1999.

3. Cancer: Principles & Practice of Oncology. 4th edition, edited by V.T. DeVita et al.,      Lippincott Co., Philadelphia, 1993. Chapters 51 and 52.

4. Cancer: Principles&Practice of Oncology. 5th edition, volume 2. Edited by Vincent T.     DeVita, Jr. et al. Lippincott-Raven Publ., Philadelphia,PA, 1997. Chapter 44,Lymphomas.

5. HY Dong et al. Mod Pathol 2001 May;14(5):472-481.

6. NL Kobrinsky et al. J Clin Oncol 2001 May 1;19(9):2390-2396.

7. Conn's Current Therapy 2004, 56th ed., Copyright © 2004 Elsevier

8. Ferri: Ferri's Clinical Advisor: Instant Diagnosis and Treatment, 2004 ed., Copyright © 2004 Mosby, Inc

Last Modified: Nov.19, 2006