Castleman Disease

Overview

Castleman Disease, also known as Castleman's disease or angiofollicular lymph node hyperplasia, is a rare and complex medical condition characterized by the abnormal growth of lymphatic cells in the lymph nodes. It was first described by Dr. Benjamin Castleman in the 1950s and can affect individuals of any age or gender. Castleman Disease is classified into two main types: unicentric Castleman Disease (UCD) and multicentric Castleman Disease (MCD).

Unicentric Castleman Disease (UCD)

UCD is the most common form of Castleman Disease and typically affects a single lymph node or a group of lymph nodes in one region of the body. It is usually localized and less aggressive than MCD. UCD is often asymptomatic or presents with mild symptoms such as painless swelling of lymph nodes, fatigue, or fever. Surgical removal of the affected lymph node(s) is the primary treatment for UCD, and the prognosis is generally excellent.

Multicentric Castleman Disease (MCD)

MCD is a more severe and systemic form of Castleman Disease in which multiple lymph nodes are involved. It is often associated with an overactive immune system and can lead to various complications. MCD is further classified into two subtypes: human herpesvirus-8 (HHV-8)-associated MCD and HHV-8-negative/idiopathic MCD. HHV-8-associated MCD is linked to the human herpesvirus-8, which is also associated with Kaposi sarcoma. Symptoms of HHV-8-associated MCD include enlarged lymph nodes, fever, night sweats, weight loss, fatigue, and various organ dysfunctions. Treatment options for HHV-8-associated MCD include antiviral therapies, immunosuppressive drugs, and targeted therapy. HHV-8-negative/idiopathic MCD is not associated with any known viral infection. It may have an autoimmune component and is associated with an overproduction of specific proteins called interleukin-6 (IL-6). Treatment for HHV-8-negative MCD focuses on managing symptoms and may involve medications such as corticosteroids, immunosuppressants, and monoclonal antibodies targeting IL-6.

Causes and Diagnosis

The exact cause of Castleman Disease is still unknown. However, certain factors, such as viral infections or autoimmune dysregulation, are believed to contribute to the development of the disease. Diagnosis of Castleman Disease involves a combination of medical history evaluation, physical examination, blood tests, imaging studies (e.g., CT scans, MRI), and biopsy of the affected lymph nodes.

Outlook

The prognosis for Castleman Disease varies depending on the subtype and extent of the disease. UCD has an excellent prognosis, with most patients experiencing complete remission after surgical removal of the affected lymph nodes. MCD, especially the HHV-8-associated subtype, is more challenging to treat, and long-term remission may be difficult to achieve. However, advancements in targeted therapies and supportive care have improved outcomes for individuals with MCD, providing hope for better disease control and quality of life.

Conclusion

Castleman Disease is a rare condition characterized by abnormal lymph node growth. It can manifest as unicentric Castleman Disease (localized) or multicentric Castleman Disease (systemic). Treatment options vary depending on the subtype, but surgery, antiviral therapy, immunosuppressants, and targeted therapies are commonly used. Ongoing research and advancements in treatment approaches continue to enhance our understanding of Castleman Disease,