Q. A 58-year-old woman visits her primary care physician with complaints of persistent right shoulder pain and a tingling sensation in her right hand over the past three months. She also reports intermittent hoarseness and shortness of breath. She has a 40-pack-year smoking history and quit smoking 2 years ago. Her vital signs are as follows: temperature 36.9°C (98.4°F), heart rate 75 beats/min, respiratory rate 18 breaths/min, blood pressure 130/80 mm Hg, and oxygen saturation 96% on room air. On physical examination, there is atrophy of the intrinsic hand muscles and weakness in her right arm. In addition, there is mild ptosis of her right eyelid. Based on the patient's presentation, what is the most likely diagnosis?