Castleman Disease

Diagnosis

To diagnose Castleman disease, your healthcare provider will review your medical history and perform a detailed physical examination. Based on initial findings, several tests may be recommended to confirm the diagnosis and determine the specific type of Castleman disease.

Blood and Urine Tests

These laboratory tests help rule out other infections or conditions that cause similar symptoms. They can also detect anemia and abnormal blood protein levels, which are often seen in people with Castleman disease.

Imaging Tests

Imaging studies are used to identify enlarged lymph nodes, as well as an enlarged liver or spleen. Common imaging techniques include:

• CT Scan: Provides detailed images of the neck, chest, abdomen, and pelvis to detect enlarged lymph nodes.

• PET Scan (Positron Emission Tomography): Helps diagnose Castleman disease and evaluate how well treatment is working.

• MRI: May be used in specific cases for detailed visualization of soft tissues.

Lymph Node Biopsy

A lymph node biopsy is essential for confirming Castleman disease. During this test, a small tissue sample is removed from an enlarged lymph node and examined under a microscope. This helps distinguish Castleman disease from related conditions such as lymphoma or other lymphatic disorders.

Treatment

Treatment for Castleman disease depends on the type of the condition—either unicentric or multicentric.

Unicentric Castleman Disease (UCD)

The standard treatment for unicentric Castleman disease is surgical removal of the affected lymph node.

• Surgery: Often curative, especially when the diseased lymph node is completely removed. However, if the lymph node is located deep within the chest or abdomen, major surgery may be required.

• Medication: If surgery is not possible, medicines typically used for multicentric Castleman disease (MCD) may be prescribed.

• Radiation Therapy: Used in rare cases where surgery and medication are ineffective.

Although surgery usually cures UCD, regular follow-up exams and imaging tests are important to monitor for recurrence.

HHV-8–Positive Multicentric Castleman Disease (MCD)

For people diagnosed with HHV-8–positive MCD, the first-line treatment is usually rituximab (Rituxan), a targeted therapy that helps control abnormal immune cell growth.

• Rituximab: Highly effective in most patients.

• Antiviral Therapy: May be used to block the activity of HHV-8 or HIV if present.

• Chemotherapy: Sometimes used to destroy excess immune cells when the disease is more aggressive.

Idiopathic Multicentric Castleman Disease (iMCD)

For idiopathic MCD, where the cause is unknown, siltuximab (Sylvant) is the primary treatment.

• Siltuximab: The only FDA-approved medication for idiopathic MCD in the U.S. It works by blocking interleukin-6 (IL-6), a protein that drives inflammation and immune overactivity.

• Corticosteroids: Drugs like prednisone are used to reduce inflammation, especially in critically ill patients.

• Chemotherapy: May be prescribed to remove harmful immune cells in severe cases.

• Other Medications: If siltuximab is not effective, other options include rituximab (Rituxan) and sirolimus (Rapamune).

Long-Term Management

People with Castleman disease require ongoing follow-up care, including regular blood tests and imaging studies, to ensure the disease remains under control and to detect any signs of recurrence early.