Lung cancer. Gross specimen of a lung with primary cancer, resulting in the pale yellow solid tumours seen here. The tumours arose from the main bronchial airways and have invaded surrounding lung tissue. Lung cancer is the 2nd most common cancer in the UK (excluding non-melanoma skin-cancer). In most people it is related to cigarette smoking, as it most probably is in this case (you can tell by the colour of the lung). Although some people get lung cancer who have never smoked, 9 out of 10 lung cancers are caused by smoking.