Castleman disease is a rare disorder of the lymph nodes and tissues. It is also called lymphoproliferative disorder, giant lymph node hyperplasia and angiofollicular lymph node hyperplasia.
Usually benign, it is not a cancer itself, but one of its subtypes, the multicentric form, behaves like a lymphoma. In addition, many patients with Castleman disease eventually develop lymphomas later.
Causes and risk factors for Castleman disease are not well known, and there are no reliable data on its incidence in Brazil or worldwide. It is known, however, that there is a higher probability of occurrence in HIV-infected patients, and that the disease can affect children and adults.
An important aspect of Castleman disease to note is that it can severely weaken the immune system, making it more difficult to fight infections.
Types of Castleman’s Disease
Two forms of the disease are known:
- Localized disease – affects only one group of lymph nodes – most often the chest or abdomen – and is not generalized. Affected lymph nodes enlarge and may put pressure on other organs or tissues in the area where they are; and
- Multicentric disease – affects several groups of lymph nodes and may affect other organs that contain lymphoid tissue. It is more severe than localized, especially in patients with HIV.
There are also microscopic subtypes of Castleman disease – when it is classified according to the shape of the lymphoid tissue:
- Hyaline-vascular type – the most common, usually localized;
- Plasmocyte type – more likely to be multicentric; and
- Mixed type – it is the least common and presents areas of both types (localized and multicentric).
Finally, Castleman disease can be classified based on viral infections:
- HIV; and
- Human herpes virus-8 (HHV-8).
Castleman disease symptoms
Localized Castleman disease usually presents as symptoms:
Respiratory problems caused by the compression exerted on the trachea or bronchi, when the increase is in the lymph nodes of the chest; and
Pain in the abdomen and difficulty swallowing, caused by the enlargement of the abdominal lymph nodes.
In the multicentric subtype, the disease may present with the presence of nodules under the skin, especially in areas such as the neck, groin or armpits, in addition to those mentioned above.
Some symptoms are common to both forms of Castleman disease:
- Infections;
- Fever;
- Weight loss for no apparent reason;
- Fatigue;
- Night sweats; and
- Weakness and/or numbness (caused by nerve damage).
Diagnosis
It is usually diagnosed in tests done for other health problems. There are cases in which, given the discomfort caused by the symptoms, the patient decides to have a check-up in search of gastrointestinal or respiratory disorders. Physical examination usually reveals the presence of enlarged lymph nodes.
Such changes are not definitive for the diagnosis, as they are common to infections and anemia, for example. Thus, the doctor will order imaging tests, such as:
- CT scan – to check the soft tissues in detail and whether the lymph nodes or internal organs are enlarged;
- MRI – especially if the doctor is concerned about areas close to the spinal cord or brain
- Chest X-ray – to identify if there are lymph nodes in the chest affected by the disease (usually ordered when the patient has respiratory problems as a symptom);
- Abdominal ultrasound – to identify if there are any lymph nodes in the abdomen affected by the disease; and
- PET-Scan – useful for finding small growths in lymph nodes and tissue that do not show up on CT scans.
In some cases, the doctor may order a lymph node biopsy to make the diagnosis of Castleman disease.
Treatment
Treatment approaches for Castleman disease include surgery, radiation therapy, and chemotherapy, among other medications.
In the case of localized Castleman disease, patients are usually cured when the affected lymph nodes are surgically removed. If it is not possible to completely solve the problem with a surgical procedure, either because of the patient’s general health conditions or because the affected lymph nodes cannot be removed completely, radiotherapy is used. The disease does not tend to come back.
On the other hand, cases of multicentric Castleman disease do not have a standardized treatment protocol. It is necessary to assess, for example, whether the disease is very widespread – which can make the specialist rule out surgery and go straight to radiotherapy or chemotherapy. If the patient has HIV, it is necessary to combine the treatment with the drugs already used to control the infection.
Castleman disease prevention
As Castleman disease has no identified cause, there are no known ways to prevent it.
