There are two main forms of lung cancer: small cell and non-small cell. The two types of lung cancer are distinguished by the way cells look and the way the cancer spreads through the body. It is important to distinguish non-small cell from small cell because the two types of cancer are treated in different ways.
Non-small cell lung cancer (NSCLC) is the most common form of lung cancer, accounting for approximately 80% of all cases. Within NSCLC, there are three major sub-types based on the histopathologic nature of the cancer:
Epidermoid or squamous carcinoma: generally arises in one of the large breathing tubes known as the bronchi and tends to grow relatively slowly.
Adenocarcinoma: generally arises near the outside surface of the lung and can vary in size and how fast it grows. Bronchioloalveolar carcinoma, or BAC, is a type of adenocarcioma that is generally considered to be resistant to chemotherapy. It presents two to six percent of all lung cancers and typically forms a line of smaller, consecutive masses.
Large cell carcinoma: may appear in any part of the lung and tends to grow and spread more quickly.
Small cell lung cancer(SCLC) is clinically and biologically distinct from NSCLC. It is considered an aggressive form on lung cancer as it is fast-growing and tends to spread though the body early in the course of the disease. SCLC account for 10% to 15% of all lung cancers.
For information on diagnosis, staging and treatment of non-small cell and small cell lung cancer visit the Bonnie J. Addario Lung Cancer Foundation.