A 51 year old woman presents to the emergency department with sudden-onset breathlessness and right-sided pleuritic chest pain. She is a non-smoker with no significant occupational exposures and no significant past medical history. She requires 40% oxygen to maintain her saturations at 92%, apyrexial, BP 101/62 mmHg, pulse 112 beats/min, respiration rate 30 breaths/min.
The CXR shows total collapse of the right lung with the heart and mediastinum shifted to the right and tracheal deviation. This appearance is likely to have been caused by a proximal obstructing lesion such as a tumour.