Lung cancer mimicking massive pulmonary embolism

Pulmonary embolism (PE) is a common finding in patients with underlying malignancy and is the commonest cause of acute cor pulmonale. A 65-year-old woman with a background of non-small-cell lung cancer presented to the emergency department with nausea and vomiting after starting erlotinib; she was pyrexial and had raised C-reactive protein. Despite aggressive fluid resuscitation and antibiotics the patient remained tachycardic, hypotensive, profoundly hypoxic and had a persistent raised jugular venous pulse. Massive PE was therefore suspected. A bedside echocardiogram demonstrated a dilated right ventricle and evidence of pulmonary hypertension. A CT pulmonary angiogram excluded a PE but revealed progression of the right hilar tumour causing complete obstruction of the right upper and middle lobe pulmonary arteries. This case highlights an important differential diagnosis when assessing patients with an underlying intrathoracic tumour with findings suggestive of PE and the importance of obtaining further imaging before considering thrombolysis.