Abstract
Pulmonary tumor thrombotic microangiopathy (PTTM) is a cancer related complication presented with pulmonary hypoxemia and hypertension. It is pathologically characterized by tumor embolus of the peripheral lung arteries and fibro cellular intimal proliferation with eccentric luminal narrowing.
We report a case of a 68-year-old female patient with breast cancer associated with PTTM. The patient who had a 3-week history of exertional dyspnea was admitted to our hospital with a diagnosis of moderate pulmonary hypertension and severe hypoxemia. Enhanced computed tomography ruled out a diagnosis of acute pulmonary embolism, but revealed Stage IV left breast cancer with bone metastasis. PTTM was suspected and iodine density images showed poor blood flow on the peripheral lung that was compatible with PTTM. Hypoxemia rapidly progressed and she died on the tenth day of admission. The needle necropsy findings revealed tumor embolus and wall thickening of the peripheral pulmonary arteries that led to the final diagnosis of PTTM.
When observing progressing hypoxia without findings of pulmonary embolism in patients with cancer, PTTM is one of the differential diagnosis.
