Necrolytic migratory erythema

Necrolytic migratory erythema (NME) is, in most cases, associated with a glucagonoma, which is a slow growing malignant tumour predominantly arising in the α‐cells of the pancreas. The triad of an unusual dermatosis, recent‐onset diabetes and weight loss should trigger consideration of NME, although cutaneous manifestations may precede the diagnosis of glucagonoma by several years.

This chapter is set out as follows:

• Most glucagonoma's arise in the α‐cells of the pancreas, and can be part of a multiple endocrine neoplasia syndrome. Rarely, glucagon‐secreting tumours can arise at other sites eg bronchial or naso‐pharyngeal

• Similar symptoms can arise in the absence of a glucagon‐secreting tumour (Pseudoglucagonoma syndrome), secondary to pancreatic insufficiency, coeliac disease and intestinal malabsorption syndromes, inflammatory bowel disease, cirrhosis, non‐pancreatic malignancies and the Myelodysplastic syndrome

• A glucagonoma is very rare and usually affects adults over the age of 50

• There is often a delay in diagnosis as patients usually present with nonspecific complaints, such as weight loss, diabetes, diarrhoea, and stomatitis, additionally early cutaneous lesions may be mild and histology non-diagnostic. Over time skin lesions become more uncomfortable

• Other features may include venous thrombosis, neurological and psychiatric symptoms

Distribution

• Can involve any site but it most often affects the perineum, buttocks, groin, lower abdomen, and lower extremities, areas subject to greater pressure and friction

Morphology

• Lesions wax and wane in a cycle of about 10 days, beginning with an erythematous patch that blisters centrally, erodes, and then crusts over and heals with hyperpigmentation
• They are typically annular or polycyclic and may become confluent

Other features

• May include glossitis and dry, cracked lips

• Blood tests
• May reveal diabetes mellitus, anaemia, and deranged LFTs if there is liver involvement 
• Serum glucagon levels may be very raised

• Skin biopsy
• Histology may reveal inflammation and separation of the superficial layers of the epidermis

• Once a diagnosis has been made further blood tests are required to look for evidence of a multiple endocrine neoplasia syndrome, as well as imaging studies to identify the source of the glucagonoma

• NME usually resolves once the glucagonoma has been surgically removed. However, if the tumour has already spread to other organs such as the liver, surgery is not as effective

• Chemotherapy may help some patients

• Prognosis - unfortunately, about 50% of patients die within five years of diagnosis