Acute cor pulmonale due to pulmonary tumour thrombotic microangiopathy from renal cell carcinoma.

We report the case of a previously healthy man who presented with subacute dyspnoea after a long drive. He developed hypoxic respiratory failure, thought secondary to a massive pulmonary embolism and was treated with tissue plasminogen activator but died in the hospital despite aggressive medical measures. Autopsy revealed pulmonary tumour thrombotic microangiopathy (PTTM) from papillary renal cell carcinoma. PTTM is a rare clinicopathological syndrome that clinically results in symptoms of dyspnoea and right heart failure. Pathologically, a localised paraneoplastic process evolves from tumour microemboli in the pulmonary arterioles, resulting in fibrocellular proliferation and narrowing of the vessels, causing subacute right heart failure. To our knowledge, this is the first case of PTTM due to papillary renal cell carcinoma.