Glucagonoma
Overview
Glucagonoma is a rare type of endocrine pancreatic tumor. This means it is a cancer of the glandular endocrine cells of the pancreas rather than the exocrine digestion-related pancreas cells. A "glucagonoma" is a cancer that produces too much production of a hormone called glucagon, which does reduce insulin production. Hence, glucagonoma can interfere with insulin and can give the appearance of diabetes mellitus. However, the effects of too much glucagon are not identical to having too little insulin. Ganda [1997] reports that 70-80% of glucagonoma patients have glucose intolerance. However, most are mild to moderate imbalances, making the symptoms similar to IGT or mild Type 2 diabetes.
Symptoms
The list of signs and symptoms mentioned in various sources for Glucagonoma includes the 6 symptoms listed below: * Glucose intolerance * Glucagon deficiency * Anemia * Characteristic brown-red skin rash * Smooth tongue * Lip inflammation (cheilitis)
Causes
* Exogenous insulin administration is the most common cause of hypoglycemia –Most commonly occurs in patients with known diabetes mellitus –May occur with inadequate food ingestion or excessive exercise after an insulin injection –May occur with delayed absorption of food (e.g., diabetic gastroparesis) –Rarely, may occur as part of attention seeking behavior (i.e., factitious) * Oral hypoglycemic medications (e.g., sulfonylurea) –This is especially common with severe liver disease, which prevents gluconeogenesis * Other medications (e.g., salicylates, sulfonamides, tetracyclines, warfarin, MAO inhibitors, phenothiazines) * Reactive hypoglycemia occurs 2–4 hours after meals, due to delayed and exaggerated insulin release (associated with a family history of type II diabetes) * Hypothyroidism * Malnutrition/fasting * Insulinoma/islet cell hyperplasia * Alcohol consumption * Sepsis * Renal failure * Sarcomas * Pituitary or adrenal insufficiency * Congenital hormone or enzyme defects * Severe hepatic dysfunction (e.g., hepatitis, hepatic toxins, hepatic necrosis)
Diagnosis
The list of diagnostic tests mentioned in various sources as used in the diagnosis of Glucagonoma includes: * Serum glucagon * Pancreas islet cell imaging * Pancreas islet cell biopsy .Home medical testing related to Glucagonoma: * Colon & Rectal Cancer: Home Testing o Home Colorectal Cancer Tests o Home Fecal Occult Bleeding Tests * High Cholesterol: Home Testing: o Home Cholesterol Tests o Home Triglycerides Tests o Home Blood Pressure Tests * High Blood Pressure: Home Testing o Home Blood Pressure Monitors o Home Heart Tests * Heart Health: Home Testing: o Heart Rate Monitors o Irregular Heartbeat Detection o Heart Electrocardiogram (ECG) * Thyroid: Home Testing: o Home Thyroid Function Tests o Home TSH Tests o Home Adrenal Function Tests * Diet & Weight Loss: Home Testing: o Home Weight Testing o Home Body Fat Testing (BMI) o Home Body Fat Monitoring o Home Fitness Testing * Diabetes: Related Home Testing: o Home Diabetes Tests o Home Blood Glucose Tests o Home Urine Glucose Tests o Home Urine Ketone Tests o Home Diabetes HbA1c Tests o Home Microalbumin Tests (Kidney) o Home Urine Protein Tests (Kidney) o Home Kidney Tests o Home Eye Tests
Prognosis
Prognosis of Glucagonoma: survival for 15 years is common
Treatment
* Glucose therapy (therapy goal is glucose >100 mg/dL) –Alert patients may be repleted with oral glucose (e.g., juice, glucose tablets) or IV D50 –Patients with altered consciousness require IV D50 solution –In children, use bolus of 25% dextrose –Frequently recheck blood glucose * Glucagon may be used to increase glucose release from the liver if unable to obtain IV access and the patient cannot tolerate oral glucose; less effective in alcoholic and malnourished patients * Octreotide may be used in cases of sulfonylurea-induced hypoglycemia to inhibit insulin release * Thiamine must be given with glucose in any suspected case of alcohol abuse or nutritional deficiency to avoid Wernicke's encephalopathy * Hydrocortisone should be administered if blood glucose remains persistently low to rule out adrenal insufficiency