What are the signs and symptoms of Multiple endocrine neoplasia type 1? Multiple endocrine neoplasia, type 1 (MEN1) is characterized primarily by several different types of endocrine tumors. People affected by MEN1 typically develop tumors of the parathyroid gland, the pituitary gland, and the pancreas, although other glands may be involved as well. These tumors are often "functional" and secrete excess hormones, which causes many of the different signs and symptoms of the condition. A variety of non-endocrine tumors are also found in MEN1, including lipomas (fatty tumors); and tumors of the skin or the central nervous system (brain and spinal cord). Signs and symptoms of MEN1 vary and largely depend on which endocrine glands are affected: Parathyroid tumors are present in 90% of people with MEN1 by age 20-25 years and may cause fatigue, depression, weight loss, constipation, nausea, vomiting, dehydration, kidney stones, fragile bones, and hypertension. Pituitary tumors can lead to headaches, vision problems, nausea and vomiting. In women, menstrual periods may become irregular or stop completely. Men may have decreased fertility, diminished sexual desire, and/or erectile dysfunction. Stomach, bowel or pancreas (also called the gastro-entero-pancreatic, or GEP tract) tumors can cause high blood sugar, weight loss, glossitis, anemia, diarrhea, blood clots, and skin rash. Adrenal tumors can cause a variety of symptoms depending on the type of hormones they secrete, including high blood pressure, irregular heartbeat, panic attacks, headaches, diabetes, abdominal pain, weakness, excessive hair growth, and stretch marks. Carcinoid tumors (slow-growing tumors that usually begin in the lining of the lungs or the digestive tract can cause flushing of the face and upper chest; diarrhea; and trouble breathing. The tumors that develop in MEN1 are often benign; however, in some cases, they can become malignant (cancerous). Gastrinomas (a specific type of GEP tract tumor) and carcinoid tumors are the most likely to advance to cancer. The Human Phenotype Ontology provides the following list of signs and symptoms for Multiple endocrine neoplasia type 1. If the information is available, the table below includes how often the symptom is seen in people with this condition. You can use the MedlinePlus Medical Dictionary to look up the definitions for these medical terms. Signs and Symptoms Approximate number of patients (when available) Exocrine pancreatic insufficiency 90% Hypercalcemia 90% Hyperparathyroidism 90% Abnormality of the gastric mucosa 50% Abnormality of the thyroid gland 50% Hypercortisolism 50% Multiple lipomas 50% Adenoma sebaceum - Adrenocortical adenoma - Autosomal dominant inheritance - Cafe-au-lait spot - Carcinoid tumor - Confetti-like hypopigmented macules - Diarrhea - Esophagitis - Glucagonoma - Growth hormone excess - Hypoglycemia - Insulinoma - Parathyroid adenoma - Peptic ulcer - Pituitary adenoma - Pituitary prolactin cell adenoma - Subcutaneous lipoma - Zollinger-Ellison syndrome - The Human Phenotype Ontology (HPO) has collected information on how often a sign or symptom occurs in a condition. Much of this information comes from Orphanet, a European rare disease database. The frequency of a sign or symptom is usually listed as a rough estimate of the percentage of patients who have that feature. The frequency may also be listed as a fraction. The first number of the fraction is how many people had the symptom, and the second number is the total number of people who were examined in one study. For example, a frequency of 25/25 means that in a study of 25 people all patients were found to have that symptom. Because these frequencies are based on a specific study, the fractions may be different if another group of patients are examined. Sometimes, no information on frequency is available. In these cases, the sign or symptom may be rare or common.