Top 10 Reasons to Quit Smoking With Cancer

We know that smoking causes cancer, but even if you've been diagnosed with the disease, there are still many good reasons to quit. Some of these reasons are fairly obvious since smoking increases the risk of death from all causes, and people with cancer do (and more often now) often die from conditions other than cancer.

But some of the reasons to kick the habit if you have cancer may surprise you. From the effect of smoking on treatments such as chemotherapy to the increased risk of complications (often times unpleasant), it's really worth the effort. Honestly.

 Why? Let's take a look.


Quitting Improves Cancer Survival and Lowers Recurrence

Doctor breaking cigarette


The effect of continued smoking has not been evaluated with every cancer, but from what we know based on studies of the most common cancers, it appears that kicking the habit is an easy (relatively speaking) way to raise the survival rate for many people living with cancer. With some cancers this may mean long-term survival, while with others it might only mean longer survival. But even without a longer life, the life people live is often of better quality with cigaretttes in the mix.

Lung cancer is the leading cause of cancer deaths in both men and women in the United States, and it appears that quitting at any stage of the disease can make a difference. We have known for some time that people with early-stage lung cancer have better survival rates from lung cancer (and overall survival) when they quit smoking. Recently a study looking at 250 people with advanced lung cancer found that the median survival (the amount of time at which 50 percent of people are still alive and 50 percent have died) is 28 months for those who successfully quit, but only 18 months for those who continued to smoke.Survival rates are improving for advanced lung cancer, and if that were study were repeated today it may mean even more time to spend with your loved ones.

What if you quit and then restart and quit again? After all, not everyone is successful the first time they quit. The news for those who can't quite kick the habit altogether is good as well. It was felt that there may even be a survival benefit for those who attempt to quit but are not completely successful.

For men with prostate cancer (the second leading cause of cancer deaths in men). continued smoking is associated with poorer survival as well as earlier recurrence of the disease.

Colon cancer is the third leading cause of cancer deaths in both men and women, and quitting smoking results in improved survival as well as lower recurrence rates of the disease.

For some cancers, quitting smoking can make a tremendous difference in survival odds. In a large study of people with head and neck cancer, those who quit smoking at the time of diagnosis and before treatment began had a 5-year survival rate of 55 percent versus 23 percent for those who continued to smoke.


Quitting Lowers the Risk of Death From Other Causes

Senior Couple on Shady Bench Watching Lake Boats
Willowpix / Getty Images

Quitting smoking not only improves the survival rates for most people living with cancer but improves survival rates overall.

If you are living with cancer yourself, it's easy to think of cancer as being the primary threat to your well-being, but that's not always the case. In fact, men who are diagnosed with prostate cancer today are more likely to die with prostate cancer than from prostate cancer. As more people survive and live beyond cancer, the risk of other causes of death becomes substantial.

Not only does smoking raise the risk of a multitude of other conditions (see this article on diseases caused by smoking), but smoking combined with some cancer treatments such as radiation therapy and chemotherapy can be more than additive.

In can be hard to describe how the combination of smoking and cancer treatments increases risk, so here is a hypothetical example. Say that smoking doubles the risk of a type of heart disease, and a particular chemotherapy drug doubles the risk of that same heart disease. Smoking while on chemotherapy may be more than additive when it comes to risk. Instead of adding 2 plus 2 to get a 4-fold increased risk as would seem obvious, the risk may actually be 14 times higher.

This is similar to what has been seen in cancer causes as well. Both smoking and asbestos exposure raise lung cancer risk, but the combination of both of these factors raises risk higher than would be expected by adding the risk of smoking and the risk of asbestos exposure alone.


Quitting Lowers the Risk of Surgical Complications

Surgeons working


Quitting smoking can reduce the risk of complications from surgery—complications which may be life-threatening, or at least reduce the quality of life for people who experience them.

Even before surgery has started, smoking raises the risk of complications of general anesthesia.

During surgery, smoking increases the risk of developing life-threatening heart related or respiratory complications.

After surgery, smoking results in poorer wound healing and an increased chance of developing an infection. This has not just been seen in clinical studies but makes sense from a biological perspective as well. Both nicotine and carbon monoxide cause vasoconstriction (a narrowing of blood vessels) which reduces the blood flow to tissues. Restricted blood flow at the surgical site then works to inhibit the repair of the surgical wound.


Quitting Lessens Complications and Makes Radiation Therapy Work Better

Man getting radiation


There are 3 reasons why smoking during radiation therapy is a bad idea.

1. Radiation therapy does not appear to be as effective for people who smoke

Studies tell us that people who smoke during radiation therapy do not do as well as non-smokers. For example, people with head and neck cancer who receive radiation as their primary treatment have a much poorer 5-year survival rate if they smoke, and this apparent loss of effectiveness has been noted in people with non-small cell lung cancer as well. One of the explanations behind this is that oxygenation of tissues (blood bringing oxygen to cells) is necessary for radiation therapy to have the maximum effect.When there is less blood flow to a cancer because of smoking (due to vasoconstriction or increased levels of carboxyhemoglobin,) the tumor cells are more resistant to damage caused by radiation. Stated another way, smoking results in the production of fewer cytotoxic (cell killing and damaging) free radicals from radiation (because free radical production requires oxygen). Fewer free radicals mean less DNA damage to cancer cells, which means improved survival of cancer cells. We don't want cancer cells to survive.

2. Smoking aggravates and prolongs radiation-induced complications 

Smoking results in increased side effects from radiation including conditions such as mouth sores (mucositis) loss of taste, dry mouth, radiation pneumonitis, loss of voice quality, bone and soft tissue damage, weight loss, and fatigue. In addition to a greater severity of these complications, they also last longer than they do for people who do not smoke.

3. Smoking during radiation therapy can greatly increase the risk of developing a second primary cancer

Smoking during breast cancer radiation following a mastectomy significantly increased the risk of lung cancer in one large study. Whereas the risk of lung cancer for a smoking women would ordinarily be 6 percent, this risk rose to a high as 38 percent for women who smoked while having radiation therapy to the chest for breast cancer. Similar findings were noted among people who smoked during radiation therapy for Hodgkin's disease. Radiation therapy has improved substantially since the time these studies were done (late 80's and early 90's) but the importance of the studies remains; smoking during radiation therapy is a bad idea.


Smoking Can Decrease the Effect of Chemotherapy and Raise Complications



As with radiation therapy, smoking can affect chemotherapy in a few different ways.

Smoking can decrease the effectiveness of chemotherapy. It appears that there is more than one mechanism by which smoking reduces the effect of chemotherapy (and do you really want to experience the side effects of chemotherapy knowing that it will be elss effective because you smoke?)

  • Smoking can alter the metabolism of chemotherapy drugs, resulting in either higher or lower levels of the drugs. This, in turn, could result in lower blood levels of the chemotherapy drug (which could decrease its effectiveness) or elevate blood levels of the drug (which could increase the risk of side effects and complications). For example, people who smoke while using the chemotherapy drug Camptosar (irinotecan) have lower levels of the drug in their bloodstream than non-smokers.
  • Smoking may promote the growth of tumors and increase resistance to chemotherapy due to nicotine-induced resistance to cell death (apoptosis) by affecting the ways that cells communicate with each other.

People who continue to smoke during chemotherapy often have increased side effects. Some of the chemotherapy side effects that appear to be worsened by smoking include fatigue, weight loss, and the risk of infections.

Specific chemotherapy agents may also raise the risk of complications when combined with smoking. For example, a category of chemotherapy drugs known as anthracyclines can result in damage to the heart in some people. People who smoke are more likely to develop heart damage as a side effect of these drugs than people who do not smoke.


Smoking Lowers the Effect of Targeted Therapies

Cigarette and medication on a table


An exciting advance in the treatment of cancer has been the use of targeted therapies—treatments that directly attack cancers and often cause fewer side effects than traditional chemotherapy drugs. Some of these drugs have allowed people to live much longer with cancer than would have been predicted if they had received chemotherapy alone.

Yet it appears that people who continue to smoke may have inferior outcomes when treated with targeted therapies as well. Studies looking at Tarceva (erlotinib) a targeted therapy for people with some types of non-small cell lung cancer, have noted poorer outcomes in people who continue to smoke.The reason isn't completely clear at this time, but one thought is that smoking results in a decreased amount of Tarceva present in the bloodstream, making it less effective.


Quitting Lowers the Risk of a Second Cancer

Coloured CT scan showing cancer of the liver

Studies tell us that quitting smoking at time of cancer diagnosis significantly lowers the risk of second cancers.

Before talking about second cancers it helps to clarify a few definitions. A second primary cancer is not metastases or spread from the initial cancer. Instead it refers to a completely new and separate cancer, unrelated to the original cancer. (This is in contrast to a secondary cancer which can refer to either a second primary cancer or to metastases from the first cancer.)

Not only does continuing to smoke raise the risk of a second cancer (as would be expected based on statistics and smoking alone), but the combination of smoking and some cancer treatments can raise the risk much higher than it would be for someone who smokes but has not had cancer treatments.

To understand this, it can help to review a little about how a cancer begins in the first place. Most cancers are considered to be "multifactorial" in cause, meaning that many things work together to either cause or prevent a cancer. One of the potential side effects of cancer treatments such as radiation therapy and chemotherapy is that these treatments themselves may increase the risk of a future cancer. Adding these risks to the risk created by smoking can be like the proverbial gasoline poured on a fire.

A few examples may make this easier to understand. It's been found that people with head and neck cancer who continue to smoke after diagnosis and during treatment, have a risk of developing a second cancer this is 5 times higher than that based on smoking alone. For people who smoked during treatment for Hodgkin's disease, the risk was 20 times higher than risk based on smoking alone in one study.


Quitting Smoking Improves Quality of Life

Senior woman sitting on jetty at the sea

Westend61 / Getty Images

Smoking after a diagnosis of cancer has been shown to reduce quality of life in several ways. Some of these include:

  • Energy/fatigue: Continued smoking after a diagnosis of cancer appears to increase the annoying symptom of cancer fatigue, and decrease energy levels. Since many people state that fatigue is their worst symptom of cancer, this is worth some thought.
  • Breathing: Breathing difficulties such as shortness of breath, wheezing, a cough, and hoarseness are significantly worse for people who continue to smoke.
  • Pain: Smoking after a diagnosis of cancer is linked to more pain. People who continue to smoke have been found to have more severe pain as well as greater impairment in functioning due to pain. With the current opioid epidemic, and many physicians reluctant to prescribe pain killers, it's worth noting that quitting smoking may be as effective as some drugs in reducing pain.
  • Performance status: Performance status, a measure of someone's ability to carry on day-to-day activities, is statistically reduced in people who continue to smoke after cancer.

Quitting Lowers Risk for Family and Friends

Burning cigarette


Quitting smoking certainly improves your own health with cancer, but it may improve the health of your loved ones as well. Most people are told that they need to choose to quit for themselves, but thinking about the impact of your quitting on your family can't hurt.

Secondhand smoke is responsible for a number of maladies and is estimated to cause roughly 3,000 lung cancer deaths yearly.

We've heard people who smoke quickly reply that they won't smoke around their loved ones. And this is commendable. There are still a few holes in the argument, however, as secondhand smoke is not the only concern. We are just beginning to learn about the impact of thirdhand smoke, the particles and gases that are left over on clothing and other surfaces after a cigarette is extinguished. It's too early to know the impact of this residue on exposed non-smokers, but it is thought that children are at a greater risk than adults.

What may not be so obvious is the psychological impact your smoking after cancer can have on your family. It's not just the loss of time with a loved one (due to going somewhere away from family to smoke.) One person commented that she has yet to forgive her father for not quitting after his diagnosis of cancer. She remains angry with him for continuing to smoke and possibly shortening his life for that reason. Rather than lessen with time, she is reminded at each holiday that her children may have had a grandfather had he chosen to quit. Certainly this woman has a problem to deal with, namely, she needs to learn to let go and forgive! Yet it is an important reminder that smoking can affect those around someone who smokes in ways that are beyond physical.


Quitting Saves Money That Can Be Used for Cancer Treatments

Cigarettes made from rolled 50 dollar bills


Quitting smoking can aid in cancer treatment in yet another way: It saves money! Money that could be used towards cancer treatments, or better yet, to celebrate the life you have today.

If you smoke a pack a day, that translates to around $5,000 a year. If you add in gas to get to the store, unnecessary purchases you make at the store since you are there buying cigarettes anyway, and the time you could be spending doing something else (even working), that number is much higher. Begin to add in a few other costs (think: dental bills from smoking-related dental problems) and the number climbs even more. According to the CDC, the total economic cost of smoking in the United States is more than 300 billion a year.

Cancer is expensive from both sides. The cost of medical care is higher than before cancer, while income is often lower. In the United States now, roughly 60 percent of personal bankruptcies are due to medical costs, many of these being cancer.


Quitting to Leave a Legacy

Adult handing a key to a child


Have you ever read To Kill a Mockingbird by Harper Lee? In discussions with kids in the classroom, one character is often the kindle to fiery conversation: Mrs. Henry Lafayette Dubose. Mrs. Dubose was a nasty tempered old woman, with a cantankerous personality further enhanced by her desire to withdraw from morphine at the end of life. Her character prompts the question: "Why would someone go through something horribly uncomfortable when they are going to die soon anyway?"

There are certainly many interpretations of her behavior and its effects, but it seemed old Mrs. Dubose accomplished 2 things in her quest. One was to prove to herself that she could do something very difficult before dying, but another was longer lasting. She demonstrated to others (think Scout) that the difficult was truly attainable, and we often have strength beyond what we believe we possess. Seeing that strength in others motivates us to find that strength in ourselves. 

That's perhaps a long way of saying that even if the previous 10 reasons to quit smoking with cancer aren't enough, there is yet another. A chance to witness your own strength in your lifetime, and an opportunity to impart the wisdom to your friends and family that we have strength beyond what we believe.

If you haven't yet quit, picture yourself as an ex-smoker. Can you hear your own thoughts? "I did it!" Can you hear the thoughts of your daughter? One person was so proud of her father. Even though he knew it wouldn't make much of a difference (as noted above, it can) he demonstrated how strong he was in kicking the habit. But it didn't stop there. She states that "knowing how strong my dad could be helps me know that I can be strong too. If he could quit smoking despite facing cancer, I think I can be strong enough to face____(fill in the blank.)"

This example may be a little bit unfair. Yanking on heart strings some would say. But take a moment to consider this angle as well as all the others mentioned above.

What do you want your legacy to be?

We need to add a final note. Family love should be unconditional. Those who commented about how proud they were of family members who quit emphasize that they would not love those family members the tiniest bit less if they had chosen to continue smoking. At the same time, however, those same family members may have moments, perhaps subtle and barely conscious, when a mountain in their life seems just a little easier given your example.

Are you ready to quit? The quit smoking toolbox provides information, resources, and motivation to help you begin today.

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