Unicentric Castleman disease

Alternate names

Unicentric angiofollicular ganglionic hyperplasia; Unicentric angiofollicular lymph hyperplasia; Localized Castleman disease

Definition

Unicentric Castleman disease (UCD) is a rare condition that affects the lymph nodes and related tissues. It is a form of Castleman disease that is "localized" to a single set of lymph nodes (as opposed to multicentric Castleman disease which has more widespread effects).

Cause

• The exact underlying cause of unicentric Castleman disease (UCD) is poorly understood.
• However, some scientists suspect that an increased production of interleukin-6 (IL-6) by the immune system may contribute to the development of UCD.
• IL-6 is a substance normally produced by cells within the lymph nodes that helps coordinate the immune response to infection.
• Increased production of IL-6 may result in an overgrowth of lymphatic cells, leading to many of the signs and symptoms of UCD.

Inheritance

Although the exact underlying cause of unicentric Castleman disease (UCD) is unknown, it is thought to occur sporadically in people with no family history of the condition.

Signs and symptoms

• Some people with unicentric Castleman disease (UCD) have no signs or symptoms of the condition.
• When present, symptoms are often nonspecific and blamed on other, more common conditions.
• UCD is "localized" (only affects one area of the body) and often starts as an enlarged lymph node.

Depending on the location of this enlarged node, some people may experience the following symptoms if it pushes on nearby organs and/or tissues:

• A feeling of fullness or pressure in the chest or abdomen
• Trouble eating or breathing
• Unintended weightloss
• Less commonly, fever, night sweats and weakness

Diagnosis

Some people affected by unicentric Castleman disease (UCD) do not have any specific signs or symptoms. In these cases, the enlarged lymph node may be discovered incidentally (by chance) during a routine physical examination or when an imaging study is ordered to investigate a different medical condition.

If UCD is suspected, the following tests may be recommended to help establish the diagnosis and rule out other conditions that cause similar features:

• Blood tests can be ordered to evaluate the levels of Interleukin-6 (IL-6) and other substances in the body, which can be elevated in people with UCD.
• They can also be helpful in ruling out other autoimmune conditions and infections that are associated with similar signs and symptoms
• Imaging studies (such as a CT scan, PET scan, MRI scan, and/or ultrasound) can help identify enlarged lymph node(s) and other health problems
• Lymph node biopsy is usually recommended to confirm the diagnosis

Treatment

• Unicentric Castleman disease (UCD) can usually be cured by surgically removing the enlarged lymph node.
• If surgery isn't an option or the lymph node can not be removed completely, radiation therapy may be recommended to shrink and/or destroy the affected tissue.

Prognosis

• The long-term outlook (prognosis) for people with unicentric Castleman disease (UCD) is generally excellent.
• In many cases, the condition can be cured by surgically removing the affected lymph node.
• In fact, one study found that disease-free survival in people with UCD following surgery was approximately 93%.