Pulmonary Tumor Thrombotic Microangiopathy Diagnosed Antemortem and Treated with Combination Chemotherapy

A 29-year-old man developed a persistent dry cough. Chest high-resolution computed tomography (HRCT) revealed centrilobular ultrafine granular shadows scattered in all lung fields. A lung biopsy with video-assisted thoracoscopic surgery revealed findings compatible with pulmonary tumor thrombotic microangiopathy (PTTM). However, the primary tumor was not identified. Combination chemotherapy with S-1 and cisplatin decreased his cough and improved the chest HRCT findings. The illness, however, gradually became difficult to control. He eventually developed pulmonary hypertension and died. Typically, an antemortem diagnosis of PTTM cannot be made. In this case, the diagnosis of PTTM and combination chemotherapy improved the chest HRCT findings, respiratory symptoms, and prognosis.