Types - Non-Small Cell
The overwhelming majority of lung cancers are carcinomas, or malignancies that arise from epithelial cells. Among these, types of lung carcinomas fall into two classifications based on the size of the malignant cells as seen under a microscope by a histopathologist. These classifications are important for determining prognoses and cancer management possibilities.
Non-small cell lung carcinoma is a type of cancer that accounts for roughly 70% of lung cancer. The term roughly describes three sub classifications of the cancer that are similar in prognosis prediction and management. The three main sub-types are squamous cell lung carcinoma, adenocarcinoma, and large cell lung carcinoma.
Accounting for roughly 30 percent of lung cancers are sqamous cell lung carcinomas. This type of cancer typically originates near the central bronchus. Cavitation and necrosis, or accidental cell death of cells are common indications of this variety. This is one of the less aggressive varieties as well developed squamous cells tend to grow much slower than other types of cancers.
Another roughly 30 percent of lung cancers can be attributed to a variety known as Adenocarcinoma, which is the type most commonly associated with smoking. However rare though, among non-smokers and those who have never smoked, Adenocarcinoma is also the most common form of lung cancer. Among female non-smokers there is a type of adenocarcinoma known as brochiolalveolar carcinoma. Accounting for close to 10 percent all lung cancers is the somewhat rarer large cell lung carcinoma which is often difficult to identify early, but the nature its growth is quite aggressive so it tends to metastasize earlier than other non-small cell lung carcinomas.
As a general rule, prognoses for those diagnosed with non-small cell lung carcinoma are quite poor. Five year survival rates with those stage 1A disease and complete surgical resection are 67% in the United States. For those with stage 1B, those numbers dwindle to 57%. For those whose cancer is detected extremely late, at stage IV, five year survival rates are just 1%. According to the American Cancer Society, the mean age of incidence in cancer discovery is age 70, with the mean age of cancer death at 71.