Extraperitoneal Presentation of Pseudomyxoma Peritonei as a Pleural Effusion: A Case Report

Pseudomyxoma peritonei (PMP) can occur in the pleural cavity presenting as pleural effusion, either as a primary disease of mucin producing adenocarcinomas of the lung or as a metastasis from PMP originating in the peritoneum. We report the case of a 64-year-old male with metastatic poorly differentiated mucinous adenocarcinoma of the lung who progressed and developed a pleural effusion that proved to be hemorrhagic pseudomyxoma in the pleura in the absence of abdominal manifestations.