Smoking and Cancer
Cancer refers to diseases in which abnormal cells divide out of control and are able to invade other tissues. Cancer cells can spread to other parts of the body through the blood and lymph systems.1,2
There are more than 100 different types of cancer. Most cancers are named for the organ or type of cell in which they start—for example, lung cancer begins in the lung and laryngeal cancer begins in the larynx (voice box).1
Symptoms can include:3
- A thickening or lump in any part of the body
- Weight loss or gain with no known reason
- A sore that does not heal
- Hoarseness or a cough that does not go away
- A hard time swallowing
- Discomfort after eating
- Changes in bowel or bladder habits
- Unusual bleeding or discharge
- Feeling weak or very tired
Smoking can cause cancer and then block your body from fighting it:4
- Poisons in cigarette smoke can weaken the body’s immune system, making it harder to kill cancer cells. When this happens, cancer cells keep growing without being stopped.
- Poisons in tobacco smoke can damage or change a cell's DNA. DNA is the cell's "instruction manual" that controls a cell's normal growth and function. When DNA is damaged, a cell can begin growing out of control and create a cancer tumor.
Doctors have known for years that smoking causes most lung cancer. It's still true today, when nearly 9 out of 10 lung cancers are caused by smoking cigarettes. In fact, smokers have a greater risk for lung cancer today than they did in 1964, even though they smoke fewer cigarettes. One reason may be changes in how cigarettes are made and what they contain.5
Treatments are getting better for lung cancer, but it still kills more men and women than any other type of cancer. More than 7,300 nonsmokers die each year from lung cancer caused by secondhand smoke.6
Smoking can cause cancer almost anywhere in your body, including the:5
- Mouth, nose, and throat
- Kidneys and ureters
- Colon and rectum
- Bone marrow and blood (leukemia)
Women smokers with breast cancer and men with prostate cancer who smoke may be more likely to die from these diseases than nonsmokers.5
Smokeless tobacco also causes cancer, including cancers of the:7
- Mouth and throat
- Within 5 years of quitting, your chance of cancer of the mouth, throat, esophagus, and bladder is cut in half.4
- Ten years after you quit smoking, your risk of dying from lung cancer drops by half.4
If nobody smoked, one of every three cancer deaths in the United States would not happen.4
The treatment for cancer depends on the type of cancer and the stage of the disease (how severe the cancer is and whether it has spread). Doctors may also consider the patient's age and general health. Often, the goal of treatment is to cure the cancer. In other cases, the goal is to control the disease or to reduce symptoms for as long as possible. The treatment plan for a person may change over time.7
Most treatment plans include surgery, radiation therapy, or chemotherapy. Some plans involve hormone therapy (a treatment to keep cancer cells from getting the hormones they need to grow). Other plans involve biological therapy (a treatment that helps your immune system fight cancer).3
Some cancers respond best to a single type of treatment. Other cancers may respond best to a combination of treatments.3
For patients who get very high doses of chemotherapy or radiation therapy, a stem cell transplant, also known as a bone marrow transplant, may be recommended by their doctor. This is because high-dose therapies destroy both cancer cells and normal blood cells. A stem cell transplant can help the body to make healthy blood cells to replace the ones lost due to the cancer treatment. It’s a complicated procedure with many side effects and risks.9
Quitting smoking improves the outlook (the prognosis) for people with cancer. People who continue to smoke after diagnosis raise their risk for future cancers and death. They are more likely to die from cancer than nonsmokers, and are more likely to develop a second (new) tobacco-related cancer.5,10
- National Cancer Institute. What Is Cancer? Defining Cancer [last updated 2014 Mar 7; accessed 2014 May 5].
- Centers for Disease Control and Prevention. Cancer Prevention [last updated 2013 May 7; accessed 2014 May 5].
- National Institute on Aging. Cancer Facts for People Over 50. [last updated 2014 Mar 24; accessed 2014 May 5].
- U.S. Department of Health and Human Services. A Report of the Surgeon General. How Tobacco Smoke Causes Disease: What It Means to You. Atlanta: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2010 [accessed 2014 May 5].
- U.S. Department of Health and Human Services. Let's Make the Next Generation Tobacco-Free: Your Guide to the 50th Anniversary Surgeon General's Report on Smoking and Health. Atlanta: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014 [accessed 2014 May 5].
- Centers for Disease Control and Prevention. Secondhand Smoke (SHS) Facts [last updated 2014 Mar 4; accessed 2014 May 5]
- World Health Organization International Agency for Research on Cancer. Smokeless Tobacco and Some Tobacco-Specific N-Nitrosamines [PDF - 3.19MB] [accessed 2014 May 5].
- Centers for Disease Control and Prevention. Poster: The Benefits of Quitting [accessed 2014 May 5].
- Centers for Disease Control and Prevention. Diamond Blackfan Anemia (DBA): Stem Cell (Bone Marrow) Transplant [last updated 2011 Jan 3; accessed 2014 May 5].
- U.S. Department of Health and Human Services. The Health Consequences of Smoking—50 Years of Progress: A Report of the Surgeon General. Atlanta: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Center for Chronic Disease Prevention and Health Promotion, Office on Smoking and Health, 2014 [accessed 2014 May 5].
Terrie smoked for 30 years.
"I’ve been diagnosed with cancer 10 times. I started smoking early. So much of what I’ve gone through — all these cancers — could have been prevented."
Real stories about cancer:
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- CDC/Office on Smoking and Health
4770 Buford Highway
Atlanta, Georgia 30341-3717