Smoking and Cancer

Autor: OncoLink Team
Fecha de la última revisión:

Most people know smoking and tobacco use can cause lung cancer, but they can also cause other illnesses:

  • Head & neck cancers (mouth, nasal cavity, throat, voice box).
  • Esophageal cancer (tube from the mouth to stomach).
  • Stomach cancer.
  • Pancreatic cancer.
  • Liver cancer.
  • Bladder cancer.
  • Kidney cancer.
  • Cervical cancer.
  • Leukemia.
  • Emphysema and COPD (chronic obstructive pulmonary disease).
  • Heart disease and peripheral vascular disease (poor circulation).
  • Stroke.
  • Diabetes.
  • Osteoporosis.

Smoking affects the health of those around you through secondhand smoke exposure. Children are more sensitive to the health effects of secondhand smoke.

How does tobacco cause cancer?

Tobacco and tobacco smoke cause cancer because they are made up of many chemicals called carcinogens (cancer-causing agents). Cigarettes, cigars, chewing and pipe tobacco are made from dried tobacco leaves. They often have ingredients added for flavor and other reasons, like making smoking more pleasant. More than 7,000 different chemicals have been found in tobacco and tobacco smoke and more than 60 are known to cause cancer.

Some of the chemicals in tobacco smoke are ammonia, arsenic, benzene (also found in pesticides and gasoline), cyanide, formaldehyde, tar, and carbon monoxide. Chemicals are also found in smokeless tobacco, like Polonium 210 (nuclear waste), cadmium (used in car batteries), lead (which causes nerve poison), nitrosamines, arsenic, and cyanide.

The chemicals in tobacco and tobacco smoke cause damage to the cells and genes in our bodies. The body has systems that manage cell growth, repair, and death. The genetic damage caused by smoking leads to uncontrolled cell growth. This uncontrolled growth can lead to tumors. These tumors can grow and spread throughout the body because they are not found or repaired by the body's normal monitoring systems.

What is my risk of getting lung cancer?

Many current and former smokers want to know their risk of lung cancer in numbers or percentages. This is very complex and is often hard to interpret- while one person may think 10% is a high chance, another thinks that 10% is a low number. For the person who is in that 10% and develops cancer, the number does not mean anything. These are numbers based on large groups of people. It can be hard to understand what that means for any one person. Don't let the number make you think that it is okay to smoke.

Researchers at Memorial Sloan Kettering Cancer Center have created an online tool that estimates risk of lung cancer in numbers for people between 50 and 80 years old who have smoked at least 20 years. They can be current or former smokers. This tool only looks at lung cancer risk and not the risk of the other types of cancer or other health conditions that smoking and tobacco cause.

You can talk with your healthcare team about your risk. Risk calculation considers the amount smoked, over what time period, and can include other parts of your health history that can increase your risk (asbestos exposure, COPD).

Risk of Other Types of Cancer

There is much less research into the risk for former smokers and other types of cancer. Quitting tobacco cannot completely erase the damage done by smoking. However, the risk of other cancers lessens as time passes without tobacco.

Is there a benefit to quitting smoking?

Yes! No matter how long or how much you have smoked, quitting lowers your risk of cancer and other smoking-related diseases. Quitting is rarely easy. Talk with your healthcare provider for help in making a quit plan. Use the links below to learn more about smoking’s health effects and quitting.

You should always be honest with healthcare providers about your smoking history and be aware of the risks of this history.

Contact your healthcare provider if you have any of the following symptoms:

  • Any change in a cough (for example, you cough up more phlegm or mucus than usual).
  • A new cough.
  • Coughing up blood.
  • Hoarseness (scratchy or weak voice).
  • Trouble breathing.
  • Wheezing.
  • Chest pain.
  • Loss of appetite.
  • Weight loss.
  • Feeling tired all the time (fatigue).
  • Frequent lung or respiratory infections (like pneumonia or bronchitis).
  • Sores or white patches in your mouth.

Smoking increases your risk of cancer and other health issues. If you want help quitting, talk to your provider about resources.

Resources for More Information:

The Benefits of Quitting Smoking

Secondhand Smoke and Health Risks

Quit Smoking: The Basics

Smoking Cessation: Where do I start?

Smoking Cessation Aids


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