Pulmonary Tumor Thrombotic Microangiopathy Caused by Metastatic Ovarian Cancer: An Antemortem Diagnosis with Pulmonary Aspiration Cytopathology.

A 48-year-old woman with advanced ovarian cancer was diagnosed with pulmonary tumor thrombotic microangiopathy (PTTM) by antemortem pulmonary wedge aspiration cytopathology. Despite the initiation of anti-cancer treatment, she unfortunately died due to progressive respiratory failure. Histopathology of the autopsied lung revealed multiple tumor embolization with fibrin-rich clot and fibro-cellular intimal proliferation at the pulmonary arteriole. The embolized tumor showed strong immune-positivity for pro-thrombotic and fibrotic factors (tissue factor and vascular endothelial growth factor), suggesting the underlying mechanisms of PTTM development. This case suggests that a quick antemortem diagnosis and the early induction of specific treatments might ensure a better prognosis of PTTM.