Continued smoking may affect cancer patients’ treatments, symptoms and side effects

A cancer diagnosis doesn’t mean it’s too late to quit smoking.

If you’re looking for a fact or statistic that illustrates how difficult it is to quit smoking, consider this: Up to two-thirds of cancer patients continue to smoke after their diagnosis and/or treatment. Even some patients diagnosed with lung cancer continue to smoke, even though smoking likely caused their cancer. Ninety percent of lung cancer cases in the United States are attributed to cigarette smoking.

It’s important for a smoker with cancer to know that the diagnosis doesn’t mean it’s too late to quit. Research is clear. If you quit smoking, even if you have cancer, you may quickly improve your health and reduce your risk of other diseases or a secondary cancer. The bodies of smokers start to heal as soon as 20 minutes after their last cigarette, according to the U.S. Centers for Disease Control and Prevention (CDC). A smoker can lower his or her risk of stroke to a nonsmoker’s risk level two to five years after quitting. The risk of developing lung cancer is cut in half ten years after a smoker quits, the CDC estimates.

Aside from increasing the risk of cancer and other diseases, smoking also may have a significant impact on cancer treatment, symptoms and side effects. 

Smoking may make cancer treatments less effective

According to the Office of Surgeon General, smoking increases the failure rate of treatments for all types of cancer. And while researchers don’t know exactly why, these reasons may play a factor:

  • Smoking may cause hypoxia, a lack of oxygen in the body or part of the body. Hypoxia may produce poorer outcomes from radiation therapy and immunotherapy.
  • Toxins in tobacco smoke may cause cellular changes that affect how chemotherapy drugs are metabolized, potentially making them more toxic or less effective.
  • Smokers may have fewer natural killer cells circulating through the body. These immune cells help limit the spread of damaged cells, including cancer cells, in the body.

Smoking may worsen cancer symptoms or treatment side effects

After examining the impact of smoking on 12 common side effects in nearly 950 patients, researchers at the University of Rochester concluded that “smoking was associated with an increased symptom burden during and following treatments for cancer.”

They also concluded that cancer patients who smoke have a lower overall quality of life than non-smoking cancer patients. Why? Smoking, cancer and cancer treatments put a tremendous burden on the body, and when combined, they may make it more difficult for the body to recover from treatment.

Some of the same smoking-related health issues that increase cancer risk—cellular changes, exposure to toxins and inflammation—may also make it more difficult to manage treatment side effects.

“ A higher symptom burden can lead to interruptions in treatment, reductions in dosages, and delays in therapy,” the researchers wrote. “Treatment interruptions and dosage reduction can, in turn, compromise treatment efficacy, resulting in lower survival rates.”

Smoking also suppresses the immune system, which may slow healing from surgery or skin issues caused by radiation therapy.

Smoking may increase the risk of a recurrence or secondary cancer

One myth worth busting: Once you get cancer from smoking, you can’t get another cancer. The link between lung cancer and smoking is well documented. But smoking also increases the risk of many cancers, including head and neck cancer and bladder cancer. That means your risk of developing bladder cancer from smoking, for instance, may not decrease because you’ve been diagnosed with lung cancer or throat cancer.

Time to quit

Quitting is the single-most important step you can take to improve the length and quality of your life, the American Lung Association© (ALA) says.

If you can’t stop cold turkey, a number of cessation methods are available to help you quit, including nicotine replacement products such as nicotine gum, patches or lollipops. Nicotine replacement therapy may also help ease withdrawal symptoms and reduce the desire to smoke. Other medications are designed to block the effects of nicotine and reduce withdrawal symptoms. Counseling may help, too.

“As we shine more light on the disastrous health effects of cigarette smoking, we need to strengthen our focus on smoking cessation programs,” says Bruce Gershenhorn, MD, Lung Cancer Program Director for Cancer Treatment Centers of America® (CTCA).

The ALA offers Freedom From Smoking® classes throughout the United States and online through its website, lung.org. As a Freedom From Smoking online member, you will also be able to speak with an ALA cessation counselor at the Lung HelpLine whenever you feel the need.

Other smoking cessation resources are available at:

More facts about smoking, cancer and your health

Here are some facts about smoking, cancer and other diseases:

  • Smoking has been linked to about a third of all cancer deaths in the United States.
  • Nearly 500,000 Americans die every year from smoking-related causes.
  • On average, non-smokers live 10 years longer than smokers.
  • Forty million Americans smoke cigarettes, and more than 16 million are living with a smoking-related disease.
  • Tobacco use remains the largest preventable cause of disease and premature death in the world. Tobacco-related causes kill more than 7 million people worldwide annually.
  • Besides cancer, tobacco use has been linked to heart disease, stroke, lung diseases, diabetes, emphysema and chronic bronchitis, tuberculosis, eye diseases, immune system issues and erectile dysfunction.

Learn eight busted myths about smoking.