Can Small Cell Lung Cancer Be Prevented

The best way to prevent lung cancer is not to smoke and to avoid breathing in other people’s smoke. If you already smoke, you should quit. Likewise, working and living in an environment free of cancer-causing chemicals will also be helpful. A healthy diet with lots of fruits and vegetables may also help prevent this cancer.

There have been many attempts to reduce the risk of lung cancer in current or former smokers by giving them high doses of vitamins or vitamin-like drugs. These have been completely unsuccessful. In one study, a nutrient related to vitamin A, called beta-carotene, appeared to increase the rate of cancer.

Some people who get lung cancer do not have any apparent risk factors. Although we know how to prevent most lung cancers, at this time we don’t know how to prevent all of them.

Risk Factors of Lung Cancer

A risk factor is anything that increases your chance of getting a disease such as cancer. Different cancers have different risk factors. For example, unprotected exposure to strong sunlight is a risk factor for skin cancer. Several risk factors can make you more likely to develop lung cancer:

Tobacco Smoking

Smoking is by far the leading risk factor for lung cancer. At the beginning of the 20th century, lung cancer was a rare disease. The introduction of manufactured cigarettes, which made them readily available, changed this. About 87% of lung cancers are thought to result from smoking and some of the rest from passive exposure to tobacco smoke. The longer you smoke and the more packs per day you smoke, the greater your risk.

If you stop smoking before a cancer develops, your damaged lung tissue gradually starts to return to normal. Ten years after stopping smoking, your risk is reduced to one-third of what it would had been if you continued to smoke. Cigar smoking and pipe smoking are almost as likely to cause lung cancer as cigarette smoking. There is no evidence that smoking low tar cigarettes reduces the risk of lung cancer. There is concern that mentholated cigarettes may increase the risk. It is thought that the menthol may allow smokers to inhale more deeply.

If you don’t smoke but breathe in the smoke of others (called secondhand smoke or environmental tobacco smoke) you are also at increased risk for lung cancer. A nonsmoker who is married to a smoker has a 30% greater risk of developing lung cancer than the spouse of a nonsmoker. Workers who have been exposed to tobacco smoke in the workplace are also more likely to get lung cancer.

Hookah smoking has become popular among young people. It is actively marketed as safer than cigarettes because the percent of tobacco in the product smoked is low and the smoke is filtered through water. It is not true that hookah smoking is safe. Studies have shown that hookah smoke contains the same cancer-causing substances as cigarettes. One study estimated that 45 minutes of hookah smoking was equal to smoking a pack of cigarettes. Furthermore, because the hookah smoke contains nicotine it is addictive and may lead to cigarette smoking in the future.

Asbestos

If you are an asbestos worker, you are about 7 times more likely to die of lung cancer. Exposure to asbestos fibers is an important risk factor for lung cancer. And if you are or have been an asbestos worker who smokes, your lung cancer risk is 50 to 90 times greater than that of people in general. Both smokers and nonsmokers exposed to asbestos also have a greater risk of developing a type of cancer that starts from the pleura (the layer of cells that line the outer surface of the lung). This cancer is called mesothelioma. Because it is usually considered a tumor of the pleura and not a type of lung cancer, mesothelioma is discussed in the American Cancer Society document, Malignant Mesothelioma.

In recent years, government regulations have nearly stopped the use of asbestos in commercial and industrial products. It is still present in many homes and commercial buildings but is not considered harmful as long as it is not released into the air by deterioration, demolition, or renovation.

Arsenic

High levels of arsenic in drinking water may increase the risk of lung cancer. This effect is even more pronounced in smokers.

Radon

When uranium breaks down naturally it produces radon, a radioactive gas that cannot be seen, tasted, or smelled. Outdoors, there is so little radon that it is not dangerous. But indoors radon can be more concentrated and become a possible risk for cancer. Recently, concerns have been raised about houses in some parts of the United States built over soil with natural uranium deposits that can create high indoor radon levels. Studies from these areas have found that the risk of lung cancer may be doubled or even tripled if you have lived for many years in a radon-contaminated house. This is a very small increase though, when it is compared to the lung cancer risk from tobacco.

Smokers are especially sensitive to the effects of radon. State and local offices of the Environmental Protection Agency can give you the names of reliable companies that perform radon testing and renovation. A document with detailed information on radon is available on request from the ACS.

Cancer-causing Agents in the Workplace

Other carcinogens (cancer-causing agents) found in the workplace that can increase your lung cancer risk include:

• radioactive ores such as uranium
• inhaled chemicals or minerals such as beryllium. vinyl chloride, nickel chromates, coal products, mustard gas, and chloromethyl ethers
• fuels such as gasoline
• diesel exhaust

The government and industry have taken major steps in recent years to protect workers. But the dangers are still present and if you work around these products, you should be very careful to avoid exposure.

Marijuana

Marijuana contains more tar than cigarettes. Marijuana is also inhaled very deeply and the smoke is held in the lungs for a long time. Marijuana is smoked all the way to the end where tar content is the highest. Many of the cancer-causing substances in tobacco are also found in marijuana. Because marijuana is an illegal substance, it is not possible to control whether it contains pesticides and other additives. Medical reports suggest marijuana may cause cancers of the mouth and throat.

It has been hard to prove a connection between marijuana and lung cancer because it is not easy to gather information about the use of illegal drugs. Also, many marijuana smokers also smoke cigarettes. This makes it difficult to know how much of the risk is from tobacco and how much is from marijuana.

Radiation Therapy to the Lungs

People who have had radiation therapy to the chest for cancer are at higher risk for lung cancer, particularly if they smoke. Typical patients are those treated for Hodgkin disease or women who receive radiation to the chest after a mastectomy for breast cancer. Women who receive radiation therapy to the breast after a lumpectomy do not have a higher than expected risk of lung cancer. But if they smoke, their chance of lung cancer goes up markedly.

Talc and Talcum Powder

In the past, some studies had suggested that talc miners and millers have a higher risk of lung cancer and other respiratory diseases because of their exposure to industrial grade talc. Recent studies of talc miners have not found an increase in lung cancer rate. Talcum powder is made from talc, a mineral that in its natural form may contain asbestos. By law since 1973, all home-use talcum products (baby, body, and facial powders) have been asbestos-free. The use of cosmetic talcum powder has not been found to increase your risk of lung cancer.

Other Mineral Exposures

People with silicosis and berylliosis (lung diseases caused by breathing in certain minerals) also have a higher risk of lung cancer.

Personal and Family History of Lung Cancer

If you have had lung cancer, you have a higher risk of developing another lung cancer. Brothers, sisters, and children of those who have had lung cancer may have a slightly higher risk of lung cancer themselves. Recently, a group called the Genetic Epidemiology of Lung Cancer Consortium studied families with a strong history of lung cancer. They found that the susceptibility to lung cancer might reside on a particular chromosome (chromosome 6). People who have this abnormality on chromosome 6 will more readily develop lung cancer even if they only smoke a little. Other family members who lack the genetic abnormality have to smoke more to develop lung cancer.

Another study, conducted in Iceland found that if a person’s first degree relative (sibling, parent) had lung cancer their chance of developing the disease doubles. Other studies have shown that the risk of lung cancer increases in a family if someone in the family developed the cancer at a young age.

Diet

Some reports have indicated that a diet low in fruits and vegetables may increase the chances of getting cancer if you are exposed to tobacco smoke. Evidence is growing that fruits and vegetables may protect you against lung cancer.

Air Pollution

In some cities, air pollution can slightly increase the risk of lung cancer. This risk is far less than that caused by smoking.

Early Detection of Lung Cancer

Usually symptoms of lung cancer do not appear until the disease is in an advanced stage. But some lung cancers are diagnosed early because they are found as a result of tests for other medical conditions. For example, a diagnosis may be made by imaging tests (such as a chest x-ray or chest CT scan), bronchoscopy (viewing the inside of bronchi through a flexible lighted tube), or sputum cytology (microscopic examination of cells in coughed up phlegm) performed for other reasons in patients with heart disease, pneumonia, or other lung conditions.

Screening Tests for Lung Cancer
Screening is the use of tests or examinations to detect a disease in people without symptoms of that disease. For example, the Pap test is used to screen for cervical cancer. Because lung cancer usually spreads beyond the lungs before causing any symptoms, an effective screening program to detect lung cancer early could save many lives.

So far there is not any lung cancer screening test that has been shown to prevent people from dying of this disease. The use of chest x-rays and sputum cytology (checking phlegm under the microscope to find cancer cells) has been tested for several years. The studies, which have been recently updated, have concluded that these tests could not find many lung cancers early enough to improve a person’s chance for a cure. For this reason, lung cancer screening is not a routine practice for the general public or even for people at increased risk, such as smokers.