A 40-year-old female patient presented with dysphagia to both liquids and solids and regurgitation for 3 months. The dysphagia was non-progressive. What is the most likely diagnosis?

Dysphagia equal for both solids and liquids from the very onset of disease suggests motor disorder like  Achalasia Diffuse esophageal spasm Dysphagia more for solids than liquids implies mechanical obstruction Ca esophagus Strictures Webs Note that dysphagia in achalasia cardia is slowly progressive. But 'nonprogressive' dysphagia in this pt. does not rule out the diagnosis of achalasia