<prompt> Achalasia is associated with increased risk of ... malignancy:Squamous cell carcinoma esophagusAdenocarcinoma esophagusBronchogenic carcinomaBronchial adenoma  <response>: Prolonged stasis esophagitis in achalasia is the likely explanation for the association between achalasia and esophageal squamous cell cancer. Squamous cell cancer esophagus risk is increased 17-fold in achalasia cardia. Ref: Harrison, Edition-18, Page-2432 