Squamous cell carcinoma originates in central bronchi, is the most common type of lung cancer in men and in smokers, is the easiest to detect early, tends to be most curable if found early, and spreads relatively slowly.

Adenocarcinoma originates in small bronchi or smaller bronchioles, is the commonest type in women and nonsmokers, often spreads to lymph glands and chest wall, and manifests itself usually late.

Large-cell carcinoma originates in outer parts of the lungs, and is the least common form of the nonsmall-cell lung cancers.

Small-cell lung cancer originates in central bronchi, is the most aggressive form of lung cancer and spreads quickly (often before symptoms appear) to the liver, bone and brain.