Several different types of cancer are grouped under the name “non-small cell lung cancer.” Together, these types make up about 85 percent of all lung cancer diagnoses. Non-small cell lung cancers share many characteristics, including prognosis and treatment.
Most cases of non-small cell lung cancer fall into one of three subtypes:
- Sqaumous cell carcinomas begin in the airways inside the lungs. This cancer appears in the cells lining the airway in the lungs.
- Adenocarcinomas grow in cells that produce mucus in the lungs. More women than men develop this type of cancer.
- Large cell carcinomas may appear in any part of the lung. This is a highly aggressive form of cancer that spreads more quickly than other non-small cell types.
Five Main Characteristics
In spite of their unique characteristics, experts group non-small cell lung cancers together because they share a number of characteristics not found in other types of cancer.
Non-small cell lung cancer can affect people of every age and ethnic group. It is found in both men and women. The most common characteristic that patients share is a history of smoking. About 80 percent of all non-small cell lung cancers are linked to smoking. Environmental causes, such as exposure to hazardous chemicals, are also prominent risk factors. In a small percentage of cases, no obvious risk factor is identified.
The main characteristic that all non-small cell lung cancers share is that they begin in the lungs or the airways leading into the lungs. These cancers first spread within the lungs, and then may metastasize, spread into the lymph system and other organs. Other forms of cancer can begin elsewhere in the body and spread to the lungs. Containing non-small cell cancer before it spreads outside the lungs can improve the outlook for the patient.
A key characteristic of non-small cell lung cancers is that they can be distinguished from the other main type of cancer by the size of the cancer cell and the prognosis for the patient. The other major type, small cell cancer, makes up 10 to 15 percent of all cancer diagnoses. This type gets its name from the smaller appearance of the cancer cells compared to other types. Small cell cancers tend to grow faster and be extremely challenging to treat.
Symptoms of non-small lung cell cancers can include coughing, wheezing, spitting up blood and pneumonia. In most cases, however, these cancers have few symptoms in the early stages. As a result, cancer may not be diagnosed until it has spread beyond the lungs. At this advanced stage, treatment is difficult.
5. Diagnosis, Treatment and Prognosis
Non-small cell lung cancers can be diagnosed early if a patient has an X-ray or imaging test for another purpose. Biopsies of lung tissue can confirm that any abnormalities found are in fact cancer.
Treatment for non-small cell cancers can involve surgery, chemotherapy and radiation. Survival rates have improved as new treatments and technologies have been developed. Five-year survival rates are still very low, however, at about 11 percent for large cell carcinomas, 15 percent for squamous cell carcinomas, and 17 percent for adenocarcinomas.