An overview of Multicentric Castleman Disease
Multicentric Castleman Disease (MCD) is a rare but potentially life-threatening condition that can occur in HIV-positive people. MCD affects the lymph nodes and tissues. causing inflammation and abnormal growth and development of lymph nodes and tissues. Although MCD is not a cancer, people with MCD are at increased risk for developing lymphoma—cancer of the immune system. MCD is often treated with chemotherapy and survival rates in the present era are generally good.
About lymph nodes and tissues
The immune system is distributed throughout the body. Parts of the immune system can be found in the following organs/tissues:
- spleen – located in the lower left-hand side of the chest
- thymus gland – located in the chest
- tonsils – at the back of the mouth
- adenoids – at the back of the nasal passages
In addition to the above locations, many lymph nodes and tissues are found in the following parts of the body:
- under the arms
- around the intestine
Lymphatic tissue can also be found near the liver.
Risk factors for MCD
Although MCD is generally uncommon, the risk for this disease is heightened in HIV-positive people. In part this risk occurs because HIV infection weakens the immune system and because many HIV-positive people, particularly men who have sex with men, are infected with a member of the herpes virus family called HHV-8. This virus has been associated with MCD in several studies. HHV-8 can infect cells of the immune system, causing them to develop abnormally.
In MCD, lymph nodes and organs (such as the spleen) or lymph tissue near the liver can become enlarged. Symptoms and laboratory tests associated with MCD are general but can include the following:
- unexpected tiredness
- unexpected weight loss
- night sweats
- loss of appetite
- swollen legs
- less-than-normal levels of red blood cells
If lymph nodes are enlarged in the chest, affected people may have difficulty breathing and may also cough. If lymph nodes in the belly are swollen, people may feel full despite needing to eat and may also have difficulty eating.
Is it MCD?
Diagnosis of MCD requires that surgeons remove a small sample of a lymph node or tissue so that it can be examined under a microscope. High-resolution CAT or MRI scans of affected parts of the body may also be ordered.
In MCD, usually more than one lymph node/tissue is affected, so combination therapy—consisting of chemotherapy and infusions of an antibody (rituximab, Rituxan) designed to attack abnormal lymphatic cells—is used.
The next report examines clinical trials exploring treatment of MCD in HIV-positive people.
— Sean R. Hosein
- Gérard L, Michot JM, Burcheri S, et al. Rituximab decreases the risk of lymphoma in patients with HIV-associated multicentric Castleman disease. Blood. 2012 Mar 8;119(10):2228-33.
- Hoffmann C, Schmid H, Müller M, et al. Improved outcome with rituximab in patients with HIV-associated multicentric Castleman disease. Blood. 2011 Sep 29;118(13):3499-503.
- Bower M, Newsom-Davis T, Naresh K, et al. Clinical Features and Outcome in HIV-Associated Multicentric Castleman's Disease. Journal of Clinical Oncology. 2011 Jun 20;29(18):2481-6.