Secondary brain cancer. Coloured coronal magnetic resonance imaging (MRI) scan through the brain of a 48-year-old smoker with metastatic (secondary) brain cancer that has spread from a primary lung cancer. The secondary cancer is in the brain's left hemisphere (round, upper right), in the parieto-occipital area. It is surrounded by peri-lesional oedema. Smoking can cause lung cancer. Once a cancer has spread, the prognosis is poor. This is a T2-weighted MRI scan with gadolinium injection.