A 55-year-old man presents with dysphagia and weight loss. The barium swallow test shows a "bird's beak" appearance. What could be the diagnosis?
Though these symptoms may initially suggest esophageal cancer, the "bird's beak" appearance on a barium swallow test points to a diagnosis of achalasia. This is a rare disorder of the esophagus characterized by a failure of the lower esophageal sphincter to relax, leading to difficulty swallowing and weight loss.