An Overview of Castleman Disease

Castleman disease (CD) is an illness that impacts the lymph nodes and associated tissues. There are two types of CD, explains the Genetic and Rare Diseases Information Center (GARD), a branch of the National Institutes of Health (NIH).

CD may be referred to by other names as well, including:

• Castleman tumor
• Angiofollicular ganglionic hyperplasia
• Angiofollicular lymph hyperplasia
• Giant benign lymphoma

One type of the disease is called unicentric CD, in which the lymph nodes affected are limited to a certain area of the body, like the chest or abdomen. The second type of CD is known as multicentric CD, and it’s not confined to a particular part of the body. In contrast, this form of the condition is found throughout the body, or systemically, impacting sets of lymph nodes and tissues from many areas, including the neck, collarbone, armpit, or groin.

The disease gets its name from Benjamin Castleman, the American physician who provided the first descriptions of the illness in the 1950s. Though CD isn’t cancer, the cells can grow and multiply in the lymphatic system in a manner that is similar to lymphoma, a cancer. A condition of the lymphatic system in which an abnormal overgrowth of cells develops is known as a lymphoproliferative disorder. Some individuals with CD may ultimately develop lymphoma, according to the American Cancer Society.

CD is considered a rare disease, with approximately 6,500–7,700 new cases per year, as reported by the Castleman Disease Collaborative Network (CDCN), a global initiative aimed at advancing research and treatment options for the illness.

Symptoms

The symptoms of CD may be vague and nonspecific to a particular disease. Additionally, some people with the disease might not be aware of any symptoms at all, with the enlarged lymph nodes being noticed during a physical exam or testing for a different condition. This is especially true in cases of unicentric CD. However, depending on the location of the enlarged lymph nodes, a person may experience signs and symptoms, such as:

• A noticeable lump on the skin
• Pain on or around the enlarged lymph nodes
• Fullness in the belly
• Breathing trouble

Typically, people with multicentric CD present with more serious symptoms, especially if the individual also has viral infections. Those symptoms can include:

• Fatigue
• Fevers
• Greater susceptibility to severe infections
• Nausea
• Weight loss
• Night sweats
• Weakness
• Anemia
• Liver or spleen becoming enlarged

Causes

To date, the specific cause of the disease remains unknown. But there’s an association between multicentric CD and immunocompromised patients, such as those living with human herpesvirus 8 (HHV-8) and human immunodeficiency virus (HIV).

Diagnosis

Since the signs and symptoms of CD overlap with other medical conditions, diagnosing it may be difficult. As mentioned, the disease is most notably found when enlarged lymph nodes are discovered during physical exams or imaging for other conditions. In many cases, the physical or medical team will rule out the possibility of other diseases before arriving at a diagnosis of CD. This may take weeks to years, according to CDNC.

However, in 2017, some strides were made in regards to diagnosing multicentric CD associated with HHV-8 with the creation of new, evidenced-based, international diagnostic criteria. When a doctor suspects a diagnosis of CD, they may order the following tests and procedures to confirm the illness.

Lymph Node Biopsy

Because the symptoms of CD are similar to other diseases that affect the lymph nodes, like lymphoma, a biopsy (removing a sample of tissue for further examination in a lab) of the enlarged lymph node will be required. A biopsy may be performed using a needle or via surgery.

Blood and Urine Tests

Blood and urine tests may reveal abnormalities, such as anemia, elevated inflammatory markers, or reduced kidney function, which can be indicative of CD. Also, blood and urine tests can be used to rule out the presence of other infections or conditions.

Imaging

Imaging tests, like magnetic resonance imaging (MRI) or positron-emission tomography (PET) scans, may be used to locate the areas of the enlarged lymph nodes in the body. Imaging tests can be used to demonstrate whether treatment is working as well.

Treatment

Treatment differs depending on whether a person has unicentric CD or multicentric CD.

Unicentric CD

In most cases of unicentric CD, surgery to remove the enlarged lymph nodes is considered the standard of care. Patients with unicentric CD may be cured if their test results return to normal ranges and they no longer have symptoms. But some patients may continue to experience unpleasant symptoms even after the surgical removal of the lymph nodes. They may require further treatment that’s similar to those with multicentric CD.

Multicentric CD

In the past, chemotherapy was used to treat multicentric CD, but other medications are emerging as a front-line treatment. Immunotherapy drugs, such as the drug Sylvant, which has Food and Drug Administration approval, are used to target an overabundance of proteins that are produced in people with multicentric MD. Other treatments can include corticosteroids to reduce inflammation, and antiviral drugs when HHV-8 or HIV is present.

If medications don’t halt the overgrowth of cells in the lymph nodes, then more aggressive therapies like chemotherapy or a bone marrow transplant from your own stem cells (known as autologous bone marrow transplant) may be warranted.

Prognosis

The CDCN reports the survival rates for a person with unicentric CD is greater than 10 years, and the life expectancy remains the same.

With the arrival of medications specifically designed to target antibodies associated with multicentric CD, the patient outcomes are expected to improve.

A Word From Verywell

Although there is still a lot to discover about CD, experts and researchers from around the world are working toward a better understanding of the disease and improving treatment options for patients.