Pancoast tumor masquerading as musculoskeletal pain.

Pancoast tumors are a rare form of non-small cell lung cancers located in the lung apex invading thoracic inlet structures and surrounding tissues. This case focuses on a 71-year-old male smoker who presented with chronic neck pain and weakness in his right arm. Imaging revealed a mass in the right lung apex that had spread to the ribs, vertebrae, and brachial plexus. A biopsy confirmed squamous cell carcinoma. Initial treatment includes chemoradiation, especially in cases where surgical resection is not recommended due to invasion of critical structures. Early recognition is crucial to avoid disease progression and to initiate appropriate oncologic management. This case emphasizes the need to consider Pancoast tumors in patients with ongoing neck and upper limb neurological symptoms, even if they do not have respiratory issues, to ensure quick diagnosis and treatment.