Metastatic lobular breast cancer masquerading as achalasia

Invasive lobular breast cancer has a propensity to spread to the GI tract as compared with other forms of cancer such as invasive ductal carcinoma. Endoscopists who perform E-POEM who encounter difficulty expanding the submucosal plane during E-POEM should keep malignancy and metastatic disease in mind as a rare cause of pseudoachalasia, even in the absence of nondiagnostic pre-peroral endoscopic myotomy evaluation.