Pseudoachalasia Due to Malignant Pleural Mesothelioma Involving the Esophagus

We report a rare case of pseudoachalasia secondary to malignant pleural mesothelioma involving the esophagus. A 66-year-old man presented with progressive dysphagia, weight loss, and postprandial hiccups. Endoscopic examination showed esophageal dilation with luminal narrowing at the esophagogastric junction, but no mucosal abnormalities. Computed tomography revealed an irregular-shaped mass extending from the peri-esophagogastric junction to the retroperitoneum, accompanied by pleural effusion, right-sided hydronephrosis, and multiple hepatic lesions. Endoscopic ultrasound-guided fine-needle aspiration from the mass lesion through the esophageal lumen revealed epithelioid malignant mesothelioma. This case highlights the importance of considering malignant mesothelioma in the differential diagnosis of pseudoachalasia, particularly when imaging reveals extrinsic esophageal compression without mucosal lesions.