Lung cancer is a prevalent form of cancer that ranks as the second most common worldwide. The lungs are vital organs that enable us to breathe, and there are two primary types of primary lung cancer: non-small cell lung cancer (NSCLC) and small cell lung cancer (SCLC).
NSCLC is the most frequent type of lung cancer, comprising three main types: adenocarcinoma, squamous cell carcinoma, and large cell lung cancer. Adenocarcinoma is the most common type of NSCLC, arising from cells that produce mucus, and typically affects the outer regions of the lungs. Despite smoking being the leading cause, adenocarcinoma is more frequently observed in non-smokers. Squamous cell carcinoma develops in the cells lining the airways and is predominantly found in the central airways of the lungs. In contrast, large cell lung cancer is a rare type of NSCLC that typically begins in the middle of the lungs.
SCLC receives its name from its appearance under a microscope and accounts for approximately 15% of lung cancers.
In some cases, cancer that originated elsewhere in the body may metastasize to the lungs, leading to lung metastases or secondary lung cancer. Moreover, cancer affecting the pleura, the lining that covers the lungs, is referred to as pleural mesothelioma.
It’s worth noting that some individuals may develop other types of cancer that start in the lungs, such as neuroendocrine tumours. Although rare, these tumours sometimes originate in the lungs. For more information about neuroendocrine tumours, refer to additional resources.