Castleman Disease: Causes, Symptoms, and Treatment

Medically reviewed by Achuta Uppu, MD, Internal Medicine. Last reviewed: October 23, 2026.

What kind of doctor treats Castleman Disease?

A hematologist (a blood doctor) or an oncologist (a cancer doctor) usually leads care for Castleman disease. It is rare, so most patients see these specialists at a medical center. A direct primary care or concierge doctor can be a first stop for an evaluation and can refer you to a specialist when needed.

What is Castleman disease?

Castleman disease is a rare blood disease defined by enlarged lymph nodes. It is first classified based on the number of regions of enlarged lymph nodes.

There are two main types. Unicentric Castleman disease affects one group of lymph nodes in one part of the body, usually in the chest or abdomen. Multicentric Castleman disease affects lymph nodes in several regions of the body at once and also causes body-wide inflammation.

Symptoms

Many people with unicentric Castleman disease have no symptoms at all. When symptoms happen, they tend to be mild. They come from fast-growing lymph nodes pressing on surrounding structures. Less commonly, some people have whole-body symptoms such as fever, fatigue, drenching night sweats, weight loss, or skin rash.

Multicentric Castleman disease can cause symptoms such as:

  • Fever, fatigue, weight loss, night sweats, and loss of appetite.
  • Enlarged lymph nodes in several regions of the body.
  • An enlarged spleen or liver.
  • Swelling in the legs or fluid buildup in the abdomen or around the lungs.
  • Anemia (a low number of red blood cells) or abnormal platelet counts.
  • Numbness in the hands and feet.
  • Kidney problems.

Causes and who gets it

Some cases of multicentric disease are linked to a virus called HHV-8. This virus causes few problems in most people. But it can cause illness in people with a weak immune system, such as people with HIV. Many other cases have no known cause.

Research also points to a substance called IL-6. The immune system uses IL-6 to fight infection. Too much of it may drive the disease in some patients. About 4,300 to 5,200 cases are diagnosed each year in the United States. It affects people of any age and both sexes.

How doctors diagnose it

Castleman disease is hard to diagnose because it mimics other illnesses. Doctors often rule out other diseases first. The key test is a biopsy. A whole lymph node is removed and looked at under a microscope. Doctors also order blood tests. These check blood counts, inflammation markers, and HIV and HHV-8. Imaging scans such as X-rays or PET-CT scans can find enlarged nodes.

Treatment

Treatment depends on the type. For unicentric disease, surgery to remove the enlarged node or nodes is the first-line treatment. It usually cures the disease, but it can come back in rare cases. When surgery is not safe or possible, options include close monitoring if there are no symptoms, partial surgery, rituximab (a drug that depletes B cells, a type of immune cell), radiation, or other treatments.

For idiopathic multicentric disease, the first-line treatment is a drug called siltuximab. It blocks IL-6. Tocilizumab is used if siltuximab is not available. Siltuximab is the only FDA-approved drug for this form. For HHV-8-related multicentric disease, rituximab works well. Some people also need antivirals or chemotherapy. Severe disease that keeps getting worse on siltuximab may be treated with strong steroids or chemotherapy.

When to see a doctor

See a doctor if you have lymph nodes that are growing quickly. Also see a doctor for fever, night sweats, or unexplained weight loss. Call 911 or go to the emergency room if you have shortness of breath or a sudden, intense onset of symptoms, because severe disease can cause life-threatening organ dysfunction. Multicentric disease can turn life threatening when it harms the organs.

How a direct primary care or concierge doctor fits in

A direct primary care doctor charges a flat monthly fee instead of billing insurance, while a concierge doctor usually charges more and often works alongside insurance. Castleman disease is rare and mimics other illnesses. A doctor with more time can follow up closely, track blood tests, and coordinate referrals to a hematologist.

Common questions

Is Castleman disease cancer?

No. It is a rare disorder in which benign (not cancer) growths form in lymph node tissue. It can also mimic lymphoma, a cancer of the lymph nodes, which is why a biopsy is needed. Over time, unicentric disease can sometimes turn into cancers such as lymphoma.

Can Castleman disease be cured?

Unicentric disease is usually cured by surgery that removes the affected node or nodes. Many people with idiopathic multicentric disease who respond to siltuximab have long-term responses. Rituximab is highly effective for the HHV-8-related type. Siltuximab is the only FDA-approved medicine for idiopathic multicentric disease.

What is the difference between the two types?

Unicentric disease affects one node or one region of nodes and often causes no symptoms. Multicentric disease affects nodes in several regions and causes body-wide inflammation with fevers, swelling, and blood count changes.

People with HIV are at increased risk, because HIV weakens the immune system's ability to control the HHV-8 virus. This form is also seen in others whose immune defenses are lowered.

Sources

  1. NORD - Castleman Disease - Symptoms, Causes, Treatment
  2. National Cancer Institute - Definition of Castleman disease

Medical Disclaimer

This content is for general educational and informational purposes only and is not medical advice. It is not a substitute for professional medical advice, diagnosis, or treatment, and reading it does not create a doctor-patient relationship. Always seek the advice of your physician or another qualified health provider with any questions about a medical condition, and never disregard or delay seeking professional advice because of something you read here. If you think you may have a medical emergency, call 911 (or your local emergency number) immediately.