MEN-1 Syndrome (Wermer Syndrome)
•Autosomal Dominant syndrome
•2/1 lakh population Prevalence.
•80% cases have Truncated menin protein** and result in oncogenesis
•Affects 3 P- Parathyroid (90%-MC), Pituitary and Pancreas.
•90% have Hyperparathyroidism due to Multiglandular hyperplasia*
•2nd MC manifest is Neuroendocrine tumor of Pancreas and Duodenum.
•Carcinoids in Thymus and Bronchus
•Pituitary adenomas- MC prolactinoma (15%-30%)
•Male and Female equally affected.
•MC pancreatic tumor is Gastrinoma**
•MC cause of mortality in MEN-1 is NET from Duodenal and pancreatic
tumors or Intra thoracic carcinoids.
•MEN 1 manifests from age of 5 years*
•Biochemical surveillance to start at below given ages:
~5 years: Prolactin level
~8 years: PTH and Calcium Level
~20 years: Gastrin, Chromogranin, Glucagon and Proinsulin
•MC manifest in MEN -1
•Due to multiglandular hyperplasia**
•MC in 2nd decade*
•1st Biochemical abnormality noted is Hypercalcemia*
•Enlargement is asymmetrical**(fig 1)
•Treatment: 2 options:
~Total Parathyroidectomy with heterotopic implantation of one parathyroid in Brachioradialis muscle
~Subtotal (removal of 3 and half glands)- Advantages are single incision
and absence of transient Hypocalcemia which may be seen in Total Parathyroidectomy**
Entero Pancreatic NET:
•2nd MC manifest is NET of Duodenum and Pancreas. (30-80% incidence)
•NET in MEN-1 are multifocal usually.
•MC site in Intra duodenal mucosa > Pancreas.
•CT scan, EUS, Somatostatin receptor scintigraphy (SRS) are used to localize
•SASI – Selective arterial secretagogue Injection is Invasive but most
•Most common (40-60%) NET are Gastrinomas and of them about 80%
•Of the location- Pancreatic gastrinomas produce more of liver metastasis
compared to Duodenal Gastrinomas.
•Excision is the treatment for Gastrinomas.
•Insulinomas are very less in incidence (10-25%)
•Only 10% of insulinomas are malignant.
•Anterior pituitary adenomas are 15-30% incidence in MEN-1
•MC Pituitary adenoma is Prolactinoma**-
•Clinical features: Amenorrhea, galactorrhea, hypogonadism in males*
•Acromegaly and Cushing Disease seen
•Type 2 Gastric Carcinoids
•Ependymomas of CNS
•Adreno cortical nodules and Bilateral adrenal hyperplasia (30%)