Achalasia secondary to neoplasia: a disease with a changing differential diagnosis.

Achalasia secondary to neoplasia is an uncommon entity, but recognition is paramount given the concern of missing a cancer diagnosis. Most case series of secondary achalasia occurred in prior decades raising the question of whether the underlying neoplastic causes have changed. All cases of achalasia secondary to neoplasia were reviewed at the Mayo Clinic from 2000 to the present. Cases were assessed for underlying cause of achalasia, whether achalasia was the primary presentation and demographic and clinical factors. Seventeen patients with achalasia secondary to neoplasia were identified. This was 1.5% of all patients with achalasia seen. The most common causes were adenocarcinoma of the esophagus, followed by breast and non-small cell lung cancer. No cases of gastric cancer were identified. Most patients had weight loss and rapid onset of symptoms but could not clearly be distinguished from primary achalasia. Nine patients presented with achalasia, whereas eight patients had known neoplasia. Five of these patients had a positive paraneoplastic panel suggestive of a paraneoplastic syndrome. Prognosis was generally poor except for patients with esophageal leiomyomatosis. This case series demonstrates a changing differential diagnosis for achalasia secondary to neoplasia with a higher number of patients presenting with a known primary and with a paraneoplastic syndrome. Awareness of secondary achalasia and its differentiation from primary causes is still essential.