Recurrent pulmonary embolus despite adequate anticoagulation: the case for routine cancer screening, prompted by an uncommon cause.

A middle-aged patient presented with dyspnoea, haemoptysis and weight loss following a recent admission for pulmonary embolus, diagnosed on CT pulmonary angiogram (CTPA). The patient was anticoagulated with warfarin to a therapeutic range 2-3. There was no relevant medical history. On examination, the pulse was 105 bpm and blood pressure was 70/50 mm Hg. Oxygen saturation was 94% on air. Repeat CTPA revealed extension of the clot burden, now a saddle embolus occluding pulmonary outflow. The patient underwent emergency surgical embolectomy, and histology of the excised clot revealed the underlying cause--a malignant, high-grade sarcoma of the pulmonary vasculature. The target international normalised ratio was increased to 3-4. Postoperatively, the patient developed a large malignant pericardial effusion which required urgent percutaneous drainage. The patient eventually underwent targeted chemotherapy, which extended patient survival. The patient passed away a year later from progressive right-sided heart failure as a result of cor pulmonale.