- Achalasia is usually a primary disorder of esophageal motility, but has been described in association with other pathological processes, such as malignancy. A 79-year-old man with achalasia secondary to gastric adenocarcinoma is presented. The differential diagnosis of secondary achalasia includes infectious and infiltrative disease and neuropathy, but mainly malignant diseases. The clinical criteria found for achalasia secondary to malignancy included older age at diagnosis, brief duration of symptoms, and weight loss. While upper gastrointestinal x-rays and computerized tomographic scanning may be helpful, the most reliable diagnostic tool is esophago-gastro-duodenoscopy. This is a terminal disease with short life expectancy. Yet making the correct diagnosis can save the patient from futile treatment with muscle relaxants and endoscopic balloon dilatation, the accepted therapeutic measures in primary achalasia.