What is the definition of POEMS Syndrome?
POEMS syndrome is a rare, mulitisystem disorder. POEMS stands for the disorder's features, which may include Polyneuropathy, Organomegaly, Endocrinopathy, Monoclonal gammopathy, and Skin changes. Signs and symptoms may include progressive sensorimotor polyneuropathy; enlarged liver, spleen, and/or lymph nodes; a disorder of the endocrine glands (often with multiple abnormalities); a monoclonal plasma cell proliferative disorder; and darkening of the skin (hyperpigmentation). Various other symptoms may also occur and may vary among affected people. The underlying cause of the disorder is not well understood. POEMS syndrome is a chronic disorder, with a median survival time of 8-14 years. There is no standard treatment; management depends on the underlying plasma cell disorder and may include radiation therapy, chemotherapy, and/or hematopoietic cell transplantation.
What are the alternative names for POEMS Syndrome?
- Polyneuropathy organomegaly
- Polyneuropathy, Organomegaly, Endocrinopathy, M protein, and Skin changes syndrome
- Crow-Fukase syndrome
What are the causes for POEMS Syndrome?
The cause of POEMS syndrome is not well understood. POEMS syndrome is a paraneoplastic disorder, which means that the signs and symptoms of the syndrome appear as a manifestation of the plasma cell disorder that the patient has (most patients are seen with osteosclerotic myeloma or monoclonal gammopathy of unknown significance); however, the mechanism by which this occurs is unknown. It is associated with a chronic overproduction of some substances known as pro-inflammatory cytokines (small molecules that act as messengers between cells to promote inflammation). These include interleukins (IL-1b, IL6) which are cytokines that help regulate immune responses, TNFα (Tumor Necrosis Factor alfa is a cytokine which is involved in the inflammatory process) and vascular endothelial growth factor (VEGF – a powerful vasodilator that may cause leaky blood vessels) which seem to be important in this disorder.
What is the outlook (prognosis) for POEMS Syndrome?
POEMS syndrome is a chronic condition. In many cases, there is progressive peripheral neuropathy that eventually causes mobility disability. The overall median survival has been estimated to be 13.7 years, while those with clubbing or extravascular volume overload may have median survivals of 2.6 and 6.6 years, respectively. Those who receive radiation therapy with a good response to treatment are thought to have longer survival. Death usually occurs from lack of nourishment or bronchopneumonia.
How is POEMS Syndrome diagnosed?
People who are suspected of having POEMS syndrome should first have their medical history evaluated and undergo a complete physical exam. Features suggestive of POEMS syndrome in the history include complaints of neurological symptoms, skin changes, signs of extravascular volume overload, and symptoms suggestive of an endocrine disorder (such as gynecomastia or irregular periods). A detailed physical exam should include an eye exam for papilledema; a neurologic exam; evaluation for enlargement of organs (organomegaly); examination of the skin; and evaluation for the presence of peripheral edema (swelling due to fluid accumulation), pleural or pericardial effusion (fluid build-up around the lungs or heart), ascites, clubbing (enlargement of the fingertips), heart failure, and cardiomyopathy.
A diagnosis of POEMS syndrome requires both the presence of polyneuropathy and a monoclonal plasma cell proliferative disorder, plus the presence of at least one major and one minor criterion on a physical exam, imaging, or laboratory evaluation.
Major criteria include:
- An osteosclerotic or mixed sclerotic/lytic lesion seen on plain films or CT scan measuring at least 0.8 cm in the longest dimension
- Castleman's disease
- Elevated serum or plasma vascular endothelial growth factor (VEGF) levels at least 3 to 4 times the upper limit of normal
Minor criteria include:
- Organomegaly (enlargement of the spleen, liver, or lymph nodes)
- Extravascular volume overload (peripheral edema, ascites, or pleural effusion)
- Endocrinopathy (excluding diabetes mellitus or hypothyroidism)
- Skin changes
- Thrombocytosis or polycythemia
Many affected people are initially misdiagnosed as having other disorders, such as chronic inflammatory demyelinating polyradiculoneuropathy (CIDP). In addition, a number of conditions are associated with a plasma cell disorder and polyneuropathy (with or without osteosclerotic bone lesions), and need to be distinguished from POEMS syndrome.