A 34-year-old man comes to the clinic due to frequent clumsiness. For the last 6 months, he has had repeated minor injuries from walking into doorways and stationary objects. The patient was also reprimanded at work for causing his supervisor to spill coffee when he bumped into her in the hallway. Medical history is notable for recurrent renal stones; following a subsequent diagnostic evaluation, the patient underwent definitive treatment with neck surgery 3 years ago. Family history is unavailable as the patient was adopted. Physical examination reveals bitemporal visual field defects. Cranial nerves, motor strength, and deep-tendon reflexes are otherwise normal. In addition to brain imaging, this patient should also be screened for which of the following tumors?

Question

A 34-year-old man comes to the clinic due to frequent clumsiness.  For the last 6 months, he has had repeated minor injuries from walking into doorways and stationary objects.  The patient was also reprimanded at work for causing his supervisor to spill coffee when he bumped into her in the hallway.  Medical history is notable for recurrent renal stones; following a subsequent diagnostic evaluation, the patient underwent definitive treatment with neck surgery 3 years ago.  Family history is unavailable as the patient was adopted.  Physical examination reveals bitemporal visual field defects.  Cranial nerves, motor strength, and deep-tendon reflexes are otherwise normal.  In addition to brain imaging, this patient should also be screened for which of the following tumors?

Quizplus · Accepted Answer

11ec160b_3ac6_a136_9249_29cc25a50039_MD0001_00 Multiple endocrine neoplasia type 1 (MEN1) is caused by mutations in the MEN1 tumor suppressor gene and is characterized by tumors of the parathyroid gland, pituitary, and pancreas (the "3 Ps"). Primary hyperparathyroidism is often the initial manifestation and usually presents with asymptomatic hypercalcemia or renal stones. Prolactin-secreting adenomas (prolactinomas) are the most common pituitary tumors. In premenopausal women, prolactinomas typically present with metabolic symptoms (eg, menstrual irregularities, galactorrhea); in men and postmenopausal women they usually present later when tumor enlargement leads to mass effect symptoms such as headache or bitemporal visual field defects (causing clumsiness in this patient) due to compression of the optic chiasm. Entero-pancreatic neuroendocrine tumors are the third major tumor type in MEN1. Gastrinoma (leading to Zollinger-Ellison syndrome) is the most common, followed by insulinoma and nonfunctional tumors. These tumors are often metastatic and are a frequent cause of tumor-related death in MEN1. This patient has visual field defects consistent with a pituitary mass lesion, which warrants cerebral imaging. In addition, he has a history of symptomatic hyperparathyroidism. Given these features of MEN1, he is also at increased risk for entero-pancreatic neuroendocrine tumors. (Choice A) Pheochromocytoma is an adrenal medullary tumor that occurs commonly in MEN2A and 2B. However, this patient's visual field defect suggests a pituitary tumor, which is more characteristic of MEN1 (not associated with pheochromocytoma). (Choice B) Primary bone tumors are not increased in MEN1, although malignant neuroendocrine tumors may occasionally metastasize to bone. (Choice C) The major inherited syndromes associated with breast cancer include BRCA1 and BRCA2 mutations (breast, ovarian, uterine/fallopian tube, pancreatic cancers). Less common syndromes include Cowden syndrome, Li-Fraumeni syndrome, and Peutz-Jeghers syndrome. Hyperparathyroidism and pituitary tumors are not prominent manifestations of any of these syndromes and are more consistent with MEN1. (Choice D) Familial adenomatous polyposis is associated with an increased risk of colon cancer and with adrenal adenomas and thyroid cancer. Educational objective: Multiple endocrine neoplasia type 1 syndrome is characterized by tumors of the pituitary, parathyroid gland, and pancreas (the "3 Ps"). __________ References: Clinical practice guidelines for multiple endocrine neoplasia type 1 (MEN1). (http://www.ncbi.nlm.nih.gov/pubmed/22723327)

A 34-Year-Old Man Comes to the Clinic Due to Frequent