A 60-year-old male, chronic smoker, presented with fatigue and chest pain. On examination, there was inset left eyeball with drooping upper left eyelid and reduced left pupil size. Which of the following is the most likely diagnosis in this condition?
High-Yield Explanation
Most tumors of the apex of the lung are adenocarcinomas Pancoast tumors - apical lung tumors in the superior pulmonary sulcus tend to invade the neural structures around the trachea, including the cervical sympathetic plexus. Involvement of sympathetic fibers gives rise to severe pain in the distribution of the ulnar nerve and Horner syndrome. Features of Horner syndrome are: S Sympathetic Injury A Anhidrosis M Miosis P Ptosis L Loss of ciliospinal reflex E Enophthalmos