Mechanisms:
(1) direct effect of a primary or metastatic tumor at the gastroesophageal junction
(2) direct invasion of the vagus nerve and/or myenteric plexus
(3) paraneoplastic autonomic dysfunction
Clinical features:
(1) The patient may present with progressive dysphagia, vomiting, reflux and/or weight loss.
(2) The process may be indistinguishable from true achalasia based on endoscopy, manometry or imaging studies.
(3) It may be accompanied by gastroparesis.
When to suspect pseudoachalasia:
(1) advanced age (> 60 years of age) at onset of signs and symptoms
(2) rapid weight loss or progression of symptoms
(3) difficulty in passing the endoscope through the constricted portion of the esophagus
(4) mucosal ulceration and/or nodularity at the gastroesophageal junction
(5) reduced compliance of the esophagogastric junction on manometry
(6) presence of lymphadenopathy or gastroparesis on imagng studies
(7) evidence of tumor elsewhere
(8) presence of antibodies in the serum associated with paraneoplastic autonomic dysfunction
The diagnosis can be made by endoscopic biopsy, but it may take repeated examinations for diagnostic material to be obtained. Sometimes surgical exploration is required to make the diagnosis.
