Lung cancer. Magnetic resonance imaging (MRI) scans (left and centre) and scintigram (right) of a 77 year old woman with a tumour (black) in the upper lobe of the left lung. There also appears to be another tumour in the lower abdomen. A radioactive tracer that attaches itself to the tumour cells has been injected into the patient for the MRI scan at left and the scintigram. The main cause of lung cancer is cigarette smoking. Symptoms include chest pain, shortness of breath and a cough. Treatment is with a combination of chemotherapy and radiotherapy.