Pancoast tumor presenting with multiple joint pains: a case report.

Background: Pancoast tumors represent a unique subset of lung cancers wherein a primary neoplasm arises in the lung's apex and invades the surrounding soft tissues. One of the main challenges in the diagnosis and treatment of these apical lung cancers is that they are usually not visualized on initial chest x-ray and, by the time the patient presents with symptoms, the tumor has almost always invaded nearby structures.

Case Presentation: Herein we report a case of a 58-year-old nonsmoking African American male who presented to the neurology clinic with a history of multiple chronic joint pains. The patient complained of shoulder pain that traveled into his right arm and right finger and had worsened over the past 9 months. The patient also reported decreased right proximal strength and swelling of his right hand. Magnetic resonance imaging of the shoulder and cervical region showed mild cervical spondylosis and a questionable right apical mass. A subsequent high-resolution computed tomography scan of the chest revealed a large right apical lung mass, with chest wall invasion and erosion of the adjacent ribs. Biopsy of the mass confirmed poorly differentiated non-small cell lung cancer. Radiation therapy was initiated, and the patient's pain improved significantly. Given the size of the tumor, chemotherapy was recommended by the oncology team. The patient decided against chemotherapy.

Conclusion: This case highlights the importance of early diagnosis by expanding the differential diagnosis in patients presenting with weakness, sensory loss, and shoulder pain beyond radiculopathy or joint-related diseases. A comprehensive history and careful examination may lead to an earlier diagnosis, more appropriate treatment, and better outcome in cases of Pancoast tumor presenting with neuropathic or musculoskeletal pain.