Lung Cancer Research Foundation

Types of Lung Cancer

Primary lung cancers, which originate in the lungs, are divided into two main types, Small Cell Lung Cancer (SCLC) and Non-Small Cell Lung Cancer (NSCLC). Early detection determines the type and the treatment.

Small Cell Lung Cancer
Represents about 20% of diagnosed cancers. It is often tied to smoking and because it can spread quickly is frequently treated with chemotherapy rather than surgery.

Non-Small Cell Lung Cancer
Three types of NSCLC represent approximately 80% of lung cancer diagnoses. Each develops in distinct areas of the lung, and behave in similar ways, though rate of growth varies.

Squamous Cell Carcinoma
Accounts for about 30% of all non-small cell lung cancers and is often tied to smoking. It is generally detected in one of the main airways (bronchi) and develops relatively slowly.

Adenocarcinoma
Is the most common subtype and accounts for 30-35% of all NSCLC. These types of tumors usually develop at the edges of the lungs and can also be found in cells in the airways. They are often slow growing and don't typically cause symptoms in their early stages.

Large Cell Carcinoma
Accounts for 10-20% of all NSCLC. It can occur in any part of the lung, and grows and spreads quickly. Like squamous cell carcinomas these tumors are associated with smoking.

Lung Cancers Toll

Lung cancer is the leading cause of cancer mortality in both men and women worldwide,
with 1.3 million people dying from the disease each year.

The American Cancer Society estimates that there will be 219,440 new cases of lung cancer annually
in the United States, and about 159,390 people die each year from the disease.
Lung cancer is responsible for almost 1/3 of all cancer deaths in the U.S.
Among women, lung cancer is responsible for more cancer deaths than breast cancer and all
gynecological cancers combined.
Lung cancer is often diagnosed in a late stage associating it with a poor prognosis for disease free survival.
The link between smoking and lung cancer is well established. 50% of new lung cancer cases are former
smokers. There are currently 50 million former smokers in the u.s.
Of people diagnosed with lung cancer, 15% have never smoked.

Lung cancer is seriously under-funded. The nation's research investment in lung cancer
lags dramatically behind funding for other cancers.

Lung Cancer Prevention

Risk Factors

Tobacco: There is clear-cut evidence of the link between tobacco use and lung cancer. The number of tobacco-related lung cancers is 90% for men and 78% for women in the US. People who stop smoking can lower their risk of lung cancer. Second-hand smoke or passive intake also increases the risk of lung cancer.
Environmental causes: Although there are numerous specific agents, their impact is lower than smoking. Causes include asbestos, radon, arsenic, chromium, nickel, tar and soot. Pollution may be a cause of lung cancer. Cities with higher pollution rates have higher numbers of lung cancer cases.
Beta-carotene: Studies show heavy smokers who take betacarotene supplements have higher rates of lung cancer than those who do not.
Diet and physical activity: Diets rich in fruits and vegetables can lower the risk of lung cancer. Heavy alcohol use may increase the risk of lung cancer. Exercise may reduce the risk of lung cancer, even in smokers.

Warning signs for lung cancer you should discuss with your doctor

Persistent cough, Chest pain, Weight loss and/or decreased appetite, Bloody sputum, Shortness of breath, Hoarseness, Fever for unknown reasons, Recurrent infections such as bronchitis or pneumonia.

Lung Cancer Screening

The LCRF strongly supports on-going research to determine the most effective method of screening tests to detect lung cancer in both the general population as well as high risk groups. The goal of detecting lung cancer in the early stage when it is most treatable and curable is a critical endpoint in overcoming this cancer. The NLST (National Lung Screening Trial), sponsored by the NIH and the NCI is studying over 50,000 at-risk people comparing CAT scan versus regular chest Xrays to determine the best method of early detection. The results of this study, which is still on-going, will provide definitive results to this important screening issue. Recently, a report from the I-ELCAP (International Early Lung Cancer Action Program) study showed in a non-controlled setting, that CAT scans could detect lung cancer in some risk populations. While very encouraging, the LCRF currently recommends discussion with your physician as to the most appropriate test in your specific situation while results of the NLST are still pending.

Sources:
The American Cancer Society
National Cancer Institute