A 57-year-old heavy smoker develops severe right shoulder pain radiating down the medial forearm, along with right-sided ptosis, miosis, and anhidrosis. Radiographs show an apical lung mass eroding the first and second ribs. The autonomic signs result from involvement of the:

• A Cervical sympathetic chain ✓
• B Phrenic nerve
• C Recurrent laryngeal nerve
• D Superior vena cava

Explanation

This is a Pancoast (superior sulcus) tumor, typically a squamous cell carcinoma or adenocarcinoma of the lung apex. Apical extension compresses the cervical sympathetic chain and stellate ganglion, producing ipsilateral Horner syndrome with ptosis, miosis, and anhidrosis, while brachial plexus invasion causes the ulnar-distribution arm pain. Recurrent laryngeal compression causes hoarseness, phrenic involvement causes diaphragmatic paralysis, and superior vena cava obstruction causes facial plethora, none of which match the presenting signs.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.