There are two basic types of Castleman disease:
- Unicentric Castleman disease. This localized form of the disease affects only a single gland (lymph node) in your lymphatic system.
- Multicentric Castleman disease. This type affects multiple lymph nodes and lymphatic tissues, and can severely weaken your immune system.
Multicentric Castleman disease can be further classified as:
- Multicentric Castleman disease without POEMS syndrome
- Multicentric Castleman disease with POEMS syndrome that involves areas of abnormal bone (osteosclerotic lesions)
- Multicentric Castleman disease with POEMS syndrome without osteosclerotic lesions
Unicentric Castleman disease
Many people with unicentric Castleman disease don't notice any signs or symptoms. The diseased lymph node is usually located in the chest, neck or abdomen. When signs and symptoms are present, they may include:
- A feeling of fullness or pressure in the chest or abdomen that can cause difficulty breathing or eating
- An enlarged lump under the skin in the neck, groin or armpit
- Unintended weight loss
- Less commonly, fever, night sweats and weakness
Multicentric Castleman disease
Most people with multicentric Castleman disease experience:
- Night sweats
- Fatigue and weakness
- Loss of appetite
- Unintended weight loss
- Enlarged lymph nodes, usually around the neck, collarbone, underarm and groin areas
- Enlarged liver or spleen
Other, less common symptoms include:
- Nerve damage in the hands and feet that leads to numbness (peripheral neuropathy)
- Skin rash
When to see a doctor
If you notice an enlarged lymph node on the side of your neck or in your underarm, collarbone or groin area, talk to your doctor. Also call your doctor if you experience a persistent feeling of fullness in your chest or abdomen, fever, fatigue, or unexplained weight loss.
It's not clear what causes Castleman disease. However, infection by a virus called human herpesvirus 8 (HHV-8) is associated with multicentric Castleman disease.
The HHV-8 virus has also been linked to the development of Kaposi's sarcoma, a cancerous tumor of the blood vessel walls that can be a complication of HIV/AIDS. Studies have found that HHV-8 is present in HIV-positive people who have Castleman disease, and in 40 to 50 percent of HIV-negative people with Castleman disease.
The precise role of HHV-8 is unclear. But it appears to cause malfunctioning immune system cells to reproduce rapidly. The immune system cells produce a protein called interleukin-6 (IL-6) that contributes to the overgrowth of lymphatic cells.
Castleman disease can affect anyone. But the average age of people diagnosed with unicentric Castleman disease is 35. Most people with the multicentric form are in their 50s and 60s. The multicentric form is also slightly more common in men than in women.
The only known risk factor for Castleman disease appears to be having HIV/AIDS.
People with unicentric Castleman disease usually do well once the affected lymph node is removed. However, having Castleman disease may increase your risk of lymphoma.
Complications of multicentric Castleman disease can be life-threatening and may include:
- Infection leading to the failure of multiple organs
- Cancer, such as lymphoma or Kaposi's sarcoma
The outlook for people with multicentric Castleman disease varies, depending on the nature of their disease. The presence of HIV/AIDS tends to worsen the outcome.
Research also indicates that people who have multicentric Castleman disease with POEMS syndrome that doesn't involve bone lesions may have worse outcomes, while people who have multicentric Castleman disease with the bone lesion variant of POEMS syndrome tend to do better.