A 60-year-old man comes to the emergency department because of nausea, headache, and generalized fatigue. He has smoked a pack of cigarettes daily for 30 years. He has a 3-month history of cough and weakness. Over the past month, he has had poor appetite and a 5-kg (11-lb) weight loss. Lung examination shows mildly prolonged expiration with end-expiratory wheezes. Laboratory results are as follows: Chest x-ray reveals overinflated lung fields and a 2.5-cm left hilar mass. Biopsy of the mass would most likely show which of the following?

Question

A 60-year-old man comes to the emergency department because of nausea, headache, and generalized fatigue. He has smoked a pack of cigarettes daily for 30 years. He has a 3-month history of cough and weakness. Over the past month, he has had poor appetite and a 5-kg (11-lb) weight loss. Lung examination shows mildly prolonged expiration with end-expiratory wheezes.  Laboratory results are as follows:  Chest x-ray reveals overinflated lung fields and a 2.5-cm left hilar mass.  Biopsy of the mass would most likely show which of the following?

Quizplus · Accepted Answer

Eductional Objective: Small cell lung cancer is a neuroendocrine malignancy associated with several paraneoplastic syndromes. It is the most common cause of syndrome of inappropriate antidiuretic hormone (SIADH) due to ectopic secretion of antidiuretic hormone. SIADH is characterized by hyponatremia, decreased serum osmolality, and urine osmolality >100 mOsm/kg H₂O.

A 60-Year-Old Man Comes to the Emergency Department Because of Nausea