Which endocrine abnormality is typically the FIRST and most common manifestation of multiple endocrine neoplasia type 1?
- A Gastrin-producing pancreatic neuroendocrine tumour
- B Primary hyperparathyroidism ✓
- C Prolactinoma
- D Phaeochromocytoma
Correct answer: B. Primary hyperparathyroidism
Explanation
Hyperparathyroidism due to multiglandular parathyroid hyperplasia occurs in about 90 percent of MEN1 patients and is usually the presenting lesion, often appearing in the second or third decade. Gastrinomas and prolactinomas occur in roughly 40 percent and 25 percent respectively and usually follow. Phaeochromocytoma belongs to MEN2, not MEN1, so option D is categorically wrong. Screening of MEN1 families therefore begins with annual calcium measurement.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.