Inheritance: autosomal dominant
Genetic localization: MEN1 gene 11q13 (tumor suppressor gene)
Symptom onset: usually as an adolescent or young adult, but it can appear earlier or later
Common features: > 80%
(1) parathyroid adenoma (seen in 95% or more of patients)
(2) multiple facial angiofibromata
Features in 50 - 80%
(1) collagenoma (whitish macular lesions on the trunk)
(2) enteropancreatic carcinoid tumor (functional or nonfunctional)
Features in 20 - 50%
(1) lipoma
(2) pituitary adenoma (prolactinoma, other)
(3) adrenal cortical adenoma or carcinoma
Features in 1 to 20%
(1) leiomyoma (esophagus, rectum, lung, uterus)
(2) foregut carcinoid tumor (thymic, bronchial, gastric)
(3) angiomyolipoma
Rare features (< 1%):
(1) pheochromocytoma
(2) ependymoma
Some patients will develop malignant carcinoid tumors which may be metastatic at the time of diagnosis.