Glucagonoma

A glucagonoma is a rare tumour of the pancreas that produces excess glucagon, a hormone that raises blood sugar. It arises from specialised pancreatic islet cells and is usually slow-growing, though it can be malignant. Most cases are diagnosed in mid to later adulthood.

The exact cause is not well understood, but most glucagonomas arise sporadically without a clear trigger. A small proportion occur as part of an inherited condition called multiple endocrine neoplasia type 1 (MEN1). Genetic testing may be offered if there is a relevant family history.

The classic feature is a distinctive skin rash called necrolytic migratory erythema, alongside weight loss, mild diabetes, and sometimes diarrhoea or blood clots. Symptoms often develop slowly, which can delay diagnosis for months or years. Because the skin rash is so characteristic, dermatologists sometimes make the initial diagnosis.

Yes, glucagonomas can be malignant and are often diagnosed at a stage where they have already spread, most commonly to the liver. Even so, many people live for years after diagnosis with appropriate treatment, as these tumours tend to grow slowly. Specialist neuroendocrine tumour teams manage both the tumour and its hormonal effects.

Diagnosis typically involves blood tests showing very high glucagon levels, combined with imaging such as CT, MRI, or specialised nuclear medicine scans to locate the tumour. A biopsy confirms the tissue diagnosis. Because the condition is rare, diagnosis is best managed by a specialist neuroendocrine tumour centre.

Surgery to remove the tumour is the main treatment when the disease is localised, and can be curative in some cases. For tumours that have spread, treatment options include somatostatin analogue injections to control hormone symptoms, targeted therapies, and sometimes chemotherapy. The distinctive skin rash usually improves once glucagon levels are controlled.

Complete surgical removal offers the best chance of cure when the tumour is found before it has spread. Even when the disease has spread, treatment can control symptoms and slow tumour growth for a long time, since these tumours are often slow-growing. Regular monitoring after treatment is important to check for recurrence.

Both are rare pancreatic neuroendocrine tumours, but they produce opposite effects: glucagonoma raises blood sugar and causes the characteristic skin rash, while insulinoma produces excess insulin and causes low blood sugar with symptoms like sweating, confusion, and fainting. They are diagnosed and monitored using different hormone blood tests. Treatment principles, including surgery as the main option, are broadly similar.

Recovery from pancreatic surgery typically takes several weeks to a few months, depending on the extent of surgery and whether it was performed by open or minimally invasive technique. The skin rash and other hormone-related symptoms often improve within days to weeks after successful tumour removal. Your surgical team will give a recovery timeline specific to your operation.

See a doctor if you develop an unexplained, persistent skin rash together with weight loss or new diabetes, as this combination warrants investigation. Because glucagonoma is rare, a private endocrinology or gastroenterology referral can help fast-track appropriate blood tests and imaging, often within about two weeks, compared with a longer routine NHS pathway. Early referral to a specialist neuroendocrine tumour centre improves the chances of effective treatment.