There has been no substantial improvement in the survival rate in decades, which is a reflection of both the lack of a satisfactory screening test that could detect it in the early stages and, up to the present time, the lack of truly effective treatment with clear survival benefits.
Types Non-small cell cancer contains at least three distinct types—squamous cell, large cell and adenocarcinoma—but the treatment of all three is generally similar. Squamous cell carcinoma is the most common type, but for reasons not understood adenocarcinoma is increasing in frequency.
Squamous cell (epidermoid) carcinoma of the lung is the microscopic type most frequently related to smoking. This type can be associated with spread of the tumor to regional lymph nodes and to distant sites (metastasis), but surgical removal of the tumor along with the nearby lymph nodes more often produces a cure than in other types.
Adenocarcinoma of the lung accounts for just over 30 percent of all non-small cell lung cancer cases. It is more common in women than squamous cell cancer and is the most frequent type seen in non-smokers, although it occurs in smokers as well. It is more likely than other types to be in the peripheral portions of the lung (near the edge) and therefore may invade the lining of the chest and produce fluid in the chest cavity more commonly than in other types.
Adenocarcinoma of the lung is commonly associated with spread of tumor to the brain.
