What are the other Names for this Condition? (Also known as/Synonyms)

• Angiofollicular Hyperplasia
• Angiofollicular Lymph Node Hyperplasia
• Benign Angiofollicular Hyperplasia

What is Castleman Disease? (Definition/Background Information)

• Castleman Disease (CD), a disease of lymph node and related organs, is a rare condition characterized by the abnormal proliferation of lymphocytes (a type of white blood cell)
• The condition may be localized to a single group of lymph nodes (unicentric) or may involve many lymph nodes and organs containing lymphoid tissue (multicentric)
• Enlarged lymph nodes are a common feature of this disease, and the diagnosis is usually made by a tissue biopsy
• The prognosis of Castleman Disease depends on the extent of the disease, and an individual’s response to treatment

Who gets Castleman Disease? (Age and Sex Distribution)

• Being a rare condition, the age group and sex predominance of this disease, is not established. Both children and adults can be affected by Castleman Disease
• The unicentric type is more common in the younger population, whereas older adults and those infected with HIV, are more likely to develop multicentric type of Castleman Disease
• No racial or ethnic predilection is observed

What are the Risk Factors for Castleman Disease? (Predisposing Factors)

There are no established predisposing factors associated with Castleman Disease; however, multicentric CD sometimes occurs in people with AIDS (caused by the human immunodeficiency virus).

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Castleman Disease? (Etiology)

The exact cause of Castleman Disease is unknown; though, certain theories have been proposed by some researchers. These include:

• Over-production of interleukin-6 (IL-6, a chemical made by lymphocytes in the body) causes the lymphocytes to grow and divide rapidly. Increased levels of IL-6 are often seen in the multicentric variety of CD
• Human herpes virus type 8 (HHV-8) is noted in the lymph node lymphocytes of many individuals with multicentric CD, infected by HIV. Some people with Castleman Disease also have Kaposi sarcoma (a type of cancer associated with AIDS), which is caused by the same virus. HHV-8 has been shown to cause infected cells to produce a subtype of IL-6 chemical, which further increases the suspicion of HHV-8 being the causative agent

What are the Signs and Symptoms of Castleman Disease?

The signs and symptoms of Castleman Disease include:

• Most often an enlarged lymph node may be the only form of presenting complaint in unicentric CD. Superficial lymph nodes are easily felt
• Enlarged lymph nodes in the chest or abdomen may put pressure on the adjacent structures leading to symptoms such as, breathing difficulties, fullness in the chest, difficulty in eating, pain while swallowing, etc.
• The lymph nodes in the groin, the underarm area, and the neck region, are commonly involved in multicentric CD. These are usually seen as lumps under the skin
• Involvement of lymphoid tissue in the liver and spleen results in their enlargement (called hepatomegaly and splenomegaly respectively)
• Anemia is very common in multicentric type of Castleman Disease
• Other common symptoms include: Fever, weakness, night sweats, loss of appetite, weight loss, nausea and vomiting, swelling of the legs, and skin rash

How is Castleman Disease Diagnosed?

A diagnosis of Castleman Disease is made using the following diagnostic tools:

• Physical examination and evaluation of medical history
• Blood test, such as blood culture to rule out infections

A lymph node biopsy is the most accurate test to diagnose CD. The types of lymph node biopsies used include:

• Excisional biopsy: The entire lymph node is removed under local anesthesia by making a small incision. This method is suitable for lymph nodes that are located near the skin surface
• Fine needle aspiration or core biopsy of lymph node: A hollow needle is inserted into the enlarged node and a small amount of tissue is removed (aspirated)

The biopsied sample is examined under microscope by a pathologist, to determine its histological appearance. The pathologist may find two common histological appearances, which are: Hyaline vascular type (the abnormally dividing lymphocytes have blood vessels amidst them) and plasma cell type (predominance of plasma cells, a type of immune cells which develop from B lymphocytes).

Imaging studies that could include:

• Computed Tomography (CT) scan, which helps detect any enlarged lymph nodes or organs in the body
• Magnetic resonance imaging (MRI) scan: It is very useful, when areas near the brain or spinal cord are suspected to have enlarged nodes
• An ultrasound scan can help detect enlarged lymph nodes in the abdomen. It can also look for an enlarged liver or spleen
• Positron emission tomography (PET) scan can detect small collection of fast-growing cells, which may not be seen on a CT scan
• Gallium scan: This is rarely used and is not always reliable

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Castleman Disease?

The risk of infection is high and this could be the most dangerous complication. A weak immune system makes the body prone to infections, which may be severe and may even result in death. Other complications from Castleman Disease include:

• Amyloidosis: A condition in which abnormal proteins are deposited in various tissues resulting in kidney damage, heart damage, and damage to other organs. Amyloidosis, which is seen to occur in Castleman Disease, improves when the disease is treated successfully
• Individuals with CD are at increased risk of developing lymphoma, a cancerous growth of lymphoid tissue

How is Castleman Disease Treated?

The treatment is determined on the basis of the disease type; whether Castleman Disease is localized (unicentric) or systemic (multicentric), and whether the individual is affected with HIV infection. The treatment measures include:

• Surgery: It is both a diagnostic and a treatment option with localized CD. The benefits of a surgical procedure depend on the location of the enlarged lymph node. In easily accessible sites, surgery is usually straightforward and curative
• Radiation therapy: It may be used as an alternative to surgery, in localized CD. It is also used as a part of treatment, in systemic CD. The procedure is painless and is usually administered 5 days a week, for several weeks. Skin rashes, weakness, nausea and vomiting, and a loss of appetite, are common side effects with radiation therapy
• Corticosteroid drugs: These drugs inhibit the immune system, thus decreasing the abnormal proliferation of lymphocytes. It is shown to be of help in treating the multicentric variety of CD
• Chemotherapy: Is mainly used to treat the multicentric variety of CD. It may be administered alone, or in combination with radiotherapy or corticosteroids. Castleman Disease being a rare condition, there is no sufficient information available, to support the use of any particular chemotherapeutic agent or drug. Often, combination drugs are used
• Immunotherapy: Monoclonal antibodies (that are synthesized immune proteins, designed to target specific molecules on the surface of cells), such as Rituximab is found to be helpful in treating Castleman Disease. It attaches itself to a protein called CD20, which is present on the surface of the lymphocytes, and kills the lymphocyte
• Immunomodulating agents: These groups of drugs act by affecting parts of the individual’s immune system. Thalidomide, when used in the treatment of cancer (arising from immune cells), such as lymphoma and multiple myeloma, has shown improvement of symptoms in some individuals affected by Castleman Disease. This drug causes serious birth defects in babies; hence, it should never be given to pregnant women
• Interferon: It is a protein synthesized in the body by the white blood cells and helps the immune system fight infections. The protein can be artificially synthesized. Interferon has shown to improve symptoms in a few patients with CD and hence, can be considered a treatment option. However, the use of interferon is limited, due its side effects, such as fever, headache, joint pain, and mood variations
• Use of antiviral drugs: Due to the association of Castleman Disease with HIV infection, antiviral drugs have been tried in patients with multicentric CD. Ganciclovir (an antiviral drug), has been shown to be useful in a few patients with multicentric CD and HIV-AIDS

How can Castleman Disease be Prevented?

• As many patients with HIV infection develop the multicentric variety of Castleman Disease (which is difficult to treat); the best way to prevent this, is by taking precautions against AIDS. Safe sexual practices, the use of condoms, and avoiding intravenous drug abuse, prevents AIDS from developing in those with HIV infection, which in turn reduces the incidence of CD
• The cause of unicentric Castleman Disease is unknown. Therefore, no preventive measures are available. However, early detection and treatment is the key for a complete cure of the disease

What is the Prognosis of Castleman Disease? (Outcomes/Resolutions)

• Castleman Disease has no established prognosis, given its rarity
• However, a few studies have been conducted to give an idea, on the outcome following treatment. The 3-year disease-free survival, has been estimated to be the highest in individuals with unicentric, hyaline vascular variety of CD, who are HIV negative

Additional and Relevant Useful Information for Castleman Disease:

Along with the treatment that has been discussed, there are a few more medications and substances, which are considered as complementary treatment. The use of complementary treatment does not cure Castleman Disease, but helps improve some of the symptoms. Some known complementary treatment methods include:

• Medication to reduce stress
• Acupuncture to decrease pain
• Peppermint tea for nausea

Some of these methods have been helpful, while the others have not been so effective.

Some individuals go in for alternative treatment, in the hope of finding a cure. However, alternative medicine has not proven to be effective (as compared to chemotherapy for Castleman Disease), considering current, established medical practices. The use of alternate treatment may also kill valuable therapy time, making it difficult to cure the disease later.