Former Smokers and Cancer Risk
Smoking any amount can cause damage that can lead to health problems. When you quit smoking this is a great achievement. You will see an improvement in your health and you are lowering your risk of smoking-related illnesses. Quitting smoking has health benefits that start right away and continued improvements over many years. This is true even for people who already have a smoking-related disease.
The good news is that the risk of having lung cancer and other smoking-related illnesses decreases after you stop smoking and continues to decrease as more tobacco-free time passes. The risk of lung cancer decreases over time, though it can never return to that of a never smoker. The risk also continues to decrease for the 12 other types of cancer smoking can cause, heart disease and other related illnesses.
Estimating your risk of lung cancer in numbers
Many current and former smokers want to know their risk of developing lung cancer in numbers. For example, some people want information such as "I have a 10% chance of developing the disease." Assigning a number to risk is very complicated and is often hard to interpret- while one person may think 10% is a high chance, another thinks that is a relatively low number. And for the person who is in that 10% and develops the cancer, the number is meaningless. Remember that statistics like these are numbers based on large groups of people. It can be difficult to translate what that means for any one individual. In other words, don't let the number convince you that it is okay to continue smoking.
If you are still interested in knowing some numbers, researchers at Memorial Sloan Kettering Cancer Center have developed 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, though they can be current or former smokers. Remember this tool only considers lung cancer risk and not risk of the 12 other types of cancer or other health conditions that smoking causes.
If you don't fall into that tool's population, you can talk with your provider about your risk. Calculating risk is very complicated and some researchers have spent entire careers trying to quantify an individual smoker's risk. Risk calculation takes into account 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. Unfortunately, quitting tobacco cannot completely erase the damage done from previous smoking. However, the risk of other cancers decreases as time passes without tobacco.
You should always be honest with healthcare providers about your smoking history and be aware of the risks associated with this history.
Inform 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.
- Trouble breathing.
- Chest pain.
- Loss of appetite.
- Weight loss.
- Feeling tired all the time (fatigue).
- Frequent lung or respiratory infections (like pneumonia or bronchitis).
- Development of sores or white patches in your mouth.
American Cancer Society. Benefits of Quitting Smoking Over Time.
Centers for Disease Control and Prevention. Smoking and Cancer.