Squamous cell carcinoma lung cancer, gross specimen. Squamous cell carcinoma of the lung is a non-small cell lung cancer, so-called because of the relative size of the irregularly-shaped, flat epithelial cells under the microscope. It may be treated surgically before it has spread, but has the potential to metastasize rapidly to the bone, adrenal glands, liver, small intestine and brain. It is a very common lung cancer, making up between 35% and 40% of all lung cancers in the UK. Lung cancer is the most lethal of all cancers worldwide, responsible for 1.2 million deaths annually. Smoking is a significant risk factor.