Undiagnosed gastric adenocarcinoma causing progressive respiratory failure

Abstract Pulmonary tumor thrombotic microangiopathy (PTTM) is a rare manifestation of malignancy. Pulmonary tumor emboli and associated fibrous intimal hyperplasia cause widespread pulmonary vascular stenosis/occlusion, which in turn increase pulmonary vascular resistance and lead to pulmonary hypertension. Gastric cancer is the most common underlying malignancy that leads to PTTM, and patients may present with dyspnea or other features of pulmonary hypertension prior to the diagnosis of cancer. In this short report, we describe a case of pulmonary hypertension due to gastric cancer associated PTTM. Endoscopic and histopathologic findings are shown, and a brief review of the literature is presented.