Pulmonary Tumor Thrombotic Microangiopathy Due to Gastric Cancer Diagnosed Antemortem by a Cytological Examination of Aspirated Pulmonary Artery Blood

A 66-year-old Japanese man receiving systemic chemotherapy for advanced gastric cancer presented with exertional dyspnea. D-dimer was elevated in the blood. Echocardiography revealed pulmonary hypertension, and a ventilation-perfusion scan indicated decreased perfusion in the bilateral lungs. Cardiac catheterization showed no evidence of pulmonary artery embolization and revealed cytologically confirmed adenocarcinoma. Thus, pulmonary tumor thrombotic microangiopathy (PTTM) was diagnosed. The patient died of respiratory failure on the 17th hospitalization day despite systemic chemotherapy. Retrospective serological testing revealed increased vascular endothelial growth factor in the pulmonary artery blood. This is a rare case with antemortem cytologically proven PTTM mediated by VEGF.