All of the following are features of MEN 1 syndrome except: September 2007

Ans. D: Medullary carcinoma of thyroid MEN-1/Wermer syndrome is characterized by abnormalities involving the parathyroid, pancreas and pituitary gland; thus the mnemonic device, the 3P's. Parathyroid-Hyperparathyroidism is present in 80-95% of patients. Asymptomatic hypercalcemia is the most common manifestation: about 25% of patients have evidence of nephrolithiasis or nephrocalcinosis. In contrast to sporadic cases of hyperparathyroidism, diffuse hyperplasia or multiple adenomas are more common than solitary adenomas. Pancreas-Pancreatic islet cell tumors occur in 60 to 70% of patients. Tumors are usually multicentric. Multiple adenomas or diffuse islet cell hyperplasia commonly occurs; such tumors may arise from the small bowel rather than the pancreas. About 30% of tumors are malignant and have local or distant metastases. Malignant islet cell tumors due to MEN 1 syndrome often have a more benign course than do sporadically occurring malignant islet cell tumors. About 40% of islet cell tumors originate from a beta cell, secrete insulin (insulinoma), and can cause fasting hypoglycemia. Beta-Cell tumors are more common in patients < 40. About 60% of islet cell tumors originate from nonbeta-cell elements and tend to occur in patients > 40. Non-beta-cell tumors are somewhat more likely to be malignant Pituitary-Pituitary tumors occur in 15 to 42% of MEN 1 patients. From 25 to 90% are prolactinomas. About 25% of pituitary tumors secrete growth hormone or growth hormone and prolactin. Excess prolactin may cause galactorrhea and excess growth hormone causes acromegaly clinically indistinguishable from sporadically occurring acromegaly. About 3% of tumors secrete ACTH, producing Cushing's disease. Most of the remainder are nonfunctional.