POEMS syndrome

POEMS syndrome is the acronymic name for a rare multisystem paraneoplastic disorder including the following features:

• P: polyneuropathy

• O: organomegaly

• E: endocrinopathy

• M: monoclonal gammopathy

• S: skin changes

Clinical presentation

The diagnostic criteria differ from the acronym. According to the International Myeloma Working Group, the diagnosis of POEMS requires two mandatory criteria, one major criterion, and one minor criterion ³.

Mandatory criteria:

• polyneuropathy

• monoclonal plasma cell proliferative disorder (the light chain is almost always lambda)

Major criteria:

• sclerotic bone lesions

• Castleman disease

• elevated levels of VEGF

Minor criteria:

• organomegaly (hepatomegaly, splenomegaly, or lymphadenopathy)

• extravascular volume overload (oedema, pleural effusion, or ascites)

• endocrinopathy (adrenal, thyroid, pituitary, gonadal, parathyroid, or pancreatic)

  • not satisfied by diabetes mellitus or hypothyroidism as these are common in the general population

• skin changes (hyperpigmentation, hypertrichosis, glomeruloid haemangiomata, plethora, acrocyanosis, flushing, or white nails)

• optic disc swelling

• thrombocytosis/polycythaemia

​To make the diagnosis of POEMS, these features should be temporally related and have no other attributable cause.

Radiographic features

MRI

Brain MRI discloses smooth, diffuse pachymeningeal thickening in most patients, sometimes with subdural effusions ⁴. 

Spine MRI shows thickening and enhancement of nerve roots in the branchial and lumbosacral plexi and occasionally also the intradural cauda equina nerve roots ⁴.

CT

The bones show sclerotic lesions, usually small (<1 cm) and multiple ⁵. The larger lesions can have a radiolucent centre and sclerotic margins ⁵.

Differential diagnosis

Patients with POEMS are often initially misdiagnosed with chronic inflammatory demyelinating polyneuropathy ⁴.

See also

• POEM procedure: unrelated procedure involving a oesophageal myomectomy