Tobacco use increases the risk of complications for all types of cancer treatment and may reduce the effectiveness of cancer treatment. Complications associated with smoking during specific cancer treatments include the following:
Surgery. Patients who smoke and undergo surgery have an increased risk of heart and lung complications, including problems related to general anesthesia (sedation medication given during surgery). In addition, smoking makes it more difficult for the surgical wound to heal and may increase the risk of an infection. Your doctor may recommend that you stop smoking two weeks before surgery to avoid any complications.
Radiation therapy. Radiation therapy is not as effective for patients who smoke, compared with nonsmokers or smokers who quit before treatment. Smoking during radiation therapy increases the risk of side effects , including oral mucositis (inflammation of the mouth and throat), loss of taste, xerostomia (dry mouth), weight loss, fatigue (tiredness and loss of energy), pneumonitis (inflammation of lung tissue), bone and soft tissue damage, and damaged voice quality.
Chemotherapy. Although less is known about effects of smoking during chemotherapy, smoking has the potential to increase side effects, including weight loss, cachexia (weight loss with muscle weakening), fatigue, and lung and heart problems. It may lead to an increased risk of infection. Furthermore, using tobacco while receiving chemotherapy may make the chemotherapy less effective. For example, using tobacco while taking irinotecan (Camptosar) or erlotinib (Tarceva) may lower the amount of drug in the blood, making the drug less effective.
Benefits of quitting smoking after receiving a cancer diagnosis
People with cancer who stop smoking experience many physical and psychological benefits that improve cancer treatment and overall health, including the following:
Increased survival rates. Studies have shown that a longer length of time between stopping smoking and starting cancer treatment is associated with a better prognosis (chance of recovery). Stopping smoking lowers the risk of treatment side effects and potentially improves the effectiveness of the treatment.
Decreased risk of secondary cancers. Quitting smoking, even at the time of diagnosis, significantly lowers the risk of developing secondary cancers (a different type of cancer that appears after the original cancer diagnosis). However, the length of time and the amount a person has smoked also influences the development of such cancers.
Improved quality of life. Smokers in the general population and smokers who have cancer tend to have a lower quality of life, compared with nonsmokers and former smokers.
Talking with your doctor about your tobacco use
Many people with cancer hesitate to tell a doctor about their smoking habit, worrying that the doctor may judge them or that they may receive less support for their cancer. Other people think that quitting smoking after a diagnosis of cancer is pointless because they already have cancer and that smoking can help relieve the stress of a cancer diagnosis. None of these ideas is true. In fact, there are significant health benefits of quitting smoking even after a cancer diagnosis, and your doctor and health care team are committed to helping people who want to reach that goal.
No matter what your level of tobacco use, it is important to talk with your doctor about your tobacco use behaviors. People who use tobacco products on a daily basis are addicted to nicotine. This addiction is going to make it harder to stop using tobacco, even if you are motivated to quit. Understanding your level of nicotine dependence will help the doctor determine the appropriate treatment to help you quit smoking and maintain a long-term, nicotine-free lifestyle.
Let your doctor know the following facts:
- Whether you've smoked at least 100 cigarettes in your lifetime
- Whether you currently smoke cigarettes
- Whether you smoke within the first 30 minutes after waking up
- How many years and how many cigarettes per day you've smoked regularly
- The age at which you began smoking
- How long it's been since you've last smoked regularly (if you've stopped smoking)
- How many times you have tried to quit smoking and how long you were successful in each attempt
- Whether people in your household smoke
- Whether smoking is allowed in your workplace
- Whether you use or have used forms of tobacco other than cigarettes and how often you have used them
Quitting Smoking 
Managing Stress