Antemortem diagnosis of pulmonary tumor thrombotic microangiopathy associated with gastric cancer and response to immediate chemotherapy

Pulmonary tumor thrombotic microangiopathy is a rare and fatal complication of cancer that features widespread tumor cell-derived embolisms in the small arteries and arterioles of the lung and is often associated with thrombus formation. We describe the case of a 43-year-old woman who was hospitalized with cough and respiratory distress that lasted for 2 months. Computed tomography findings demonstrated multiple areas of interlobular septal thickening and ground-glass opacities in both lungs. Transthoracic echocardiography demonstrated a D-shaped left ventricle suggesting right heart overload, and pulmonary blood flow scintigraphy revealed multiple small, peripheral, and patchy areas of reduced blood flow. Upper gastrointestinal endoscopy revealed a signet-ring carcinoma. The patient was diagnosed with pulmonary tumor thrombotic microangiopathy based on her clinical presentation and treatment with tegafur, gimeracil oteracil potassium, oxaliplatin, and an anticoagulant was initiated on the 3rd day after admission. The symptoms improved rapidly after treatment initiation. The patient was discharged 28 days after initiation of chemotherapy without the need for supplemental oxygen. This case suggests that the immediate use of chemotherapy and anticoagulants for treating pulmonary tumor thrombotic microangiopathy may improve patient survival.