The classification of lung cancer can be based upon the appearance of the cancer cells. These cells are usually microscopic. Lung cancer has been classified into two categories such as:
- Small Cell Lung Cancers (SCLC): SCLC is caused by smoking cigarettes. It is the most aggressive form of lung cancer. In this cancer, cells are rapidly growing and spread quickly to other organs of the body. SCLC accounts for about 10%-15% of lung cancers.
- Non-Small Cell Lung Cancers (NSCLC): It is the most commonly occurring form of lung cancer. It accounts for about 85% of all lung cancers. There are three main types of NSCLC:
Adenocarcinomas originate from the outer sites of the lungs. These cancers can spread to the lymphatic tissues. Bronchioloalveolar carcinoma is the subtype of adenocarcinoma that originates from multiple sites within the lungs. Upon chest X-ray it resembles pneumonia. Its prognosis is better as compared to other types of lung cancers.
Squamous Cell Carcinomas:
This type of lung cancer develops in the chest area bronchi. It usually remains within the lungs and spreads to lymph nodes. Squamous cell cancers grow large in size and form a cavity.
This type of lung cancer usually spreads to the lymph nodes and other parts of the body. It accounts for about 10%-15% of all lung carcinomas. This is the least common type of lung cancer.