The radiograph shows a right apical mass. This clinical and radiographic presentation is strongly suggestive of a Pancoast tumor. Such lung masses (typically non–small cell carcinomas) can cause brachial plexus compression when they progress, which results in thoracic outlet obstruction and symptoms similar to those seen in this patient.
The patient was admitted by a hospitalist service, and further imaging did confirm the presence of a lung mass, as well as extension to the chest wall and cervicothoracic portion of the spinal canal. CT-guided biopsy of the mass is pending.