Can You Get A Lung Transplant With Lung Cancer?

Recently, we had the opportunity to provide care for a patient in his early 60s diagnosed with severe, end-stage COPD—now categorized simply as severe COPD. Recognizing the severity of his condition, one of my more brilliant coworkers had a thought: why wouldn't he be a candidate for a lung transplant? Intrigued, my coworker delved into the intricacies of lung transplantation and uncovered a surprising answer.

As his investigation progressed, a crucial piece of information emerged—this patient had lung cancer. The revelation left my coworkers and me questioning why individuals with lung cancer are often excluded from the lung transplant list. One hypothesis we formulated was the uncertainty surrounding metastasis—after all, there's no guarantee that the cancer hasn't spread beyond the lungs.

In our exploration, we confirmed that uncertainty about metastasis was indeed one of the reasons lung cancer patients are often excluded from the transplant list. However, our journey into the intricacies of lung transplantation unveiled additional contributing factors. It became apparent that individuals undergoing lung transplants also need medications to suppress the immune response, preventing the immune system from attacking the new set of lungs. Should the lung cancer recur, the immuno-suppressed state required for organ transplantation could significantly complicate the management and treatment of the recurring cancer.

Moreover, the lung transplant waiting list is teeming with individuals eagerly awaiting this life-changing opportunity. Coupled with the inherent limitations in organ availability, the ethical dilemma intensifies. Allocating a fresh set of lungs to someone with a history of lung cancer becomes increasingly challenging, considering the pressing demand and the responsibility to maximize the benefits of available organs for the broader population.

Oxidative Stress: How Asthma, COPD, Oxygen May Increase Lung Cancer Risk

There is some evidence linking supplemental oxygen with certain cancers. So, is it true that supplemental oxygen may cause cancer? Why might this happen? Let's investigate the evidence.

In 2002, we wrote how high concentrations of oxygen were linked with cancer. That article noted that inhalation of an FiO2 of 100% for three hours increased the risk for developing cancer later in life. The reason was due to oxidative stress.

In a future post I want to investigate oxidative stress. What exactly does this do to the body? What causes it? What does it actually involve? How might it lead to cancer? So, that's a future investigation we will undertake.

For now, all you need to know is that oxygen, once it gets inside your body, splits into unpaired electrons. When a molecule has an unpaired electrons it is said to be unstable. It is referred to as a free radical. Free radicals will steal an electron from other molecules.

Under ideal circumstances, it steals an electron from an antioxidant. These are substances inside our body's meant to neutralize free radicals by donating an electron. Antioxidants can be ingested by eating certain foods, such as those containing vitamin C and E.

Sometimes, however, your body becomes overwhelmed with free radicals. There are certain disease processes that can cause this. Certain drugs can cause this, and one example is supplemental oxygen. In this case, your body becomes so overwhelmed with free radicals that they overwhelm antioxidants.

In excess, free radicals steal electrons from cells. So the cell now becomes unstable. It then it in turn steals an electron from a nearby cell. This creates a chain reaction of sorts. And this is what is referred to as oxidative stress. Cells become stressed. When this happens they release a substance called Reactive Oxygen Species (ROS). This triggers an immune response.

And, when this happens, they release chemicals such as cytokines and chemokines. These are your proinflammatory chemicals. They warn your immune system that something is wrong. And your immune cells release more cytokines and chemokines. These chemicals are helpful when you are exposed to bacteria and viruses. But, in excess, they can also be damaging to cells.

Other things that can cauuse oxidative stress like this are exposure to allergens and exposure to toxic chemicals in cigarette and wood smoke. This may explain how airways of asthmatics and COPD patients become chronically inflamed. So, it can explain many disease processes. And this includes cancers.

Oxidative stress may cause chronic inflammation. This may be what causes inflammatory diseases, such as asthma, COPD, diabetes, cardiovascular disease, and neurological diseases. And, as noted, it may also explain the links between some of these diseases and various cancers.

Under prolonged stress like this, oxidative stress is prolonged. So you end up with lots of ROS and similar substances roaming around. They can also cause gene mutations. Some of these mutations may cause the gene to produce harmful substances that may begin the cancer process.

This may explain the link between COPD and lung cancer. It actually might explain links between asthma and lung cancer. Studies show asthmatics are 2-6 times more likely to develop lung cancer than non-asthmatics. So, this may explain this link.

This is all very complex. There are very long and almost inexplicable articles on this stuff. But, my goal is to make it easy to understand. So, just keep in mind there is a lot more involved here than what I explain.

So, this may explain how long-term oxygen therapy, while relatively safe, is not without potential long-term side effects. It may also explain how those high doses of oxygen, even for short terms, may cause cancers later in life.
References.

1. Van Eaden, Stephan F., “Oxidative stress in chronic obstructive pulmonary disease: A lung and systemic process,” Canadian Respiratory Journal, Jan-Feb, 2013, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3628643/, accessed 5/28/17
2. Mandal, Anaya, “What is oxidative stress?”, News Medical Life Sciences, http://www.news-medical.net/health/What-is-Oxidative-Stress.aspx, accessed 5/28/17
3. CHSS Emory University, “What is oxidative stress,” Youtube.com. https://www.youtube.com/watch?v=9r07MhA_S9E, accessed 5/28/17
4. Kacmarek, Robert M., James K. Stoller, Albert J. Heuer, editors, “Egan’s Fundamentals of Respiratory Care,” 10th edition, 2013, Elsevier, pages 913
5. Domej, et al., “Oxidative stress and free radicals in COPD – implications and relevance for treatment,” International Journal of Chronic Obstructive Pulmonary Disease, 2014, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4207545/, accessed 5/29/17
6. "What happens in your body during oxidative stress?" HealthOlution. Youtube.com, https://www.youtube.com/watch?v=p1PEWZRHylo&t=15s, accessed 5/28/17
7. Parichha, Arpan, "Reactive oxygen species and oxidative stress," Youtube.com, https://www.youtube.com/watch?v=IhvyFBecgAY, accessed 5/2917
8. Nele, Cielen, Karen Maes, Ghislaine Gayen-Ramirez, "Musculoskeletal Disorders in Chronic Obstructive Pulmonary Disease," Biomed Research International, 2014, https://www.hindawi.com/journals/bmri/2014/965764/, 5/31/17
9. Eldridge, Lynne, "Does Asthma Increase The Risk Of Lung Cancer?" verywell health, 2017, June 19, https://www.verywellhealth.com/does-asthma-raise-the-risk-of-lung-cancer-2248983, accessed 8/19/19
10. Reuter, et al., "Oxidative stress, inflammation, cancer: How are they linked?" Free Radical Biology & Medicine, 2011, December 1, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2990475/, accessed 8/19/19

Breathalizer to screen for lung cancer?

One of the main reasons there is such a high mortality rate for lung cancer is because usually by the time it is discovered it's too late to do anything for it, or it has metastasized to other parts of the body.

Yet, according Lynn Eldridge, "Breath Test to Detect Lung Cancer a Possibility," at lungcancer.about.com, researchers in Israel Researchers in Israel "have developed an "electronic nose" - that is, an instrument that can 'smell' the breath of individuals who are healthy or have cancer, and know the difference. They found that the test could not only detect cancer, but could tell the difference between 4 different types of cancer, those being cancers of the lung, breast, colon, and prostate."

She continues, "How could a sample of exhaled air be useful in looking for cancer? Changes in genes and proteins that take place in cancer cause a change in the surface of cancer cells (the cell membrane). These changes result in the emission of volatile organic compounds (VOCs) that can be detected when someone exhales. A sensitive nanoparticle array is then used to distinguish the different VOCs found in the 4 cancers studied and in healthy individuals.

She notes that 30% of lung cancer is found in the early stages, and this test would make it so more cancer can be discovered earlier. It's possible the test could be performed at a regular annual office visit.

"As it stands," she writes, "only 30% people are diagnosed in the early stages (stage 1 and stage 2) of lung cancer; 40% have already progressed to stage 4 (metastatic) lung cancer at the time of diagnosis. And that is for non-small cell lung cancer. For small cell lung cancer, the chance of finding cancer in a curable stage is even lower."

A quick breath at an office visit may not only allow doctors to screen early lung cancer, yet monitor the course of those with the disease, and especially those in remission.

Lung Cancer: Everything RT's need to know

Figure 1

In the United States, Lung Cancer is the second most common cancer for both men and women, with breast cancer in women and prostrate cancer in men topping both lists.  It is the leading cause of cancer related deaths among both men and women.

As you can see in figure 1 to the right lung cancer rates were relatively low before smoking consumption became common around the turn of the 20th century.  It just took lung cancer 10 years to catch up with the rising number of smokers. Since then, lung cancer rates have increased or decreased in parallel fashion right alongside cigarette consumption rates.

Other than cigarette smoke, other causes of lung cancer may include genetic factors (which causes most childhood lung cancers), radon gas, asbestos, and air pollution.

Lung cancer appears to be caused when airway epithelial cells divide. Cells divide all the time without a hitch. However, certain environmental factors -- and the chemicals in cigarette smoke is one of them -- can increase the likelihood that an error will occur during cell division. 

Inside every cell in your body is a copy of your genetic code. (You can learn more about genes by checking out my article, "What are genes?" When cells divide, exact copies of your genetic code are made. This code essentially is made of genes, and each gene tells a specific cell what to do.

Some of these genes tell airway epithelial cells what to do. For instance, these cells are told to be cilia cells or to secrete mucus. Sometimes, however, during cell division, errors occur on the genes that are responsible for these actions. It is these errors, often called gene mutations, that are responsible for the development of cancer cells, including lung cancer cells.

So, rather than acting as normal airway epithelial cells, cancer cells do something abnormal. Like other cells, cancer cells can also divide, creating more and more cells that do something abnormal. This division may occur uncontrollably to form lumps or masses of tissue called tumors. These interfere with normal lung function, and they release secretions that interfere with normal lung function.

When a cancer displays limited growth and stays in one spot it's considered malignant, yet most cases of lung cancer are considered to be malignant carcinoma's of the lung.

There are two types of lung cancer, and the treatment depends on the type:

1. Small Cell Carcinoma. This is slightly more common in men than women, although it's the least common type of lung cancer. It was formally referred to as oat cell carcinoma.  It responds to radiation and chemotherapy. This is the fastest growing type of cancer, and can quickly metastasize to other parts of the body, including the brain, liver, and bone. Because it spreads so quickly, it's usually not diagnosed until it is inoperable. Prognosis tends to be grim. 
2. Non Small Cell Carcinoma. It spreads slow enough that it can often be diagnosed early and can be treated with chemotherapy, radiation, and surgery.  

Unfortunately, at the present time the five year prognosis of any type of cancer is only 14%. However, this does depend upon how early the cancer is diagnosed and how aggressively it is treated.

Symptoms are generally non-specific, and so lung cancer is usually only suspected after other probable causes are ruled out. Diagnosis is made by x-ray or cat scan, although the cancer is generally confirmed by bronchoscopy, where a lung biopsy is performed.

Symptoms may include: Bloody sputum, chest pain, bone pain, cough, loss of appetite, dyspnea, weight loss, wheezing, facial swelling, fever, dysphagia, weakness, and clubbing of the fingernails.

It causes shortness of breath because it can block the air passages in your lungs, and leaves an accumulation of secretions behind the blockage, which predisposes these patients to pneumonia. Since lung cancers have fragile surfaces and receive a good supply of blood, they are prone to producing bloody secretions.

Again, there are many causes of lung cancer, although the most common is smoking cigarettes. It is estimated that about 80% of cases of lung cancer are caused by cigarettes. Male smokers have a 17.2% risk for developing lung cancer, while female smokers have an 11.6% risk.

I just thought I'd throw this in for comparison: male nonsmokers have a 1.4% risk of developing lung cancer, an female nonsmokers have a 1.3% risk. So, this shows the significance of the graphic above, which is truly telling. This data has been used by various organizations to increase awareness of lung cancer and the need to prevent kids from smoking, and to get smokers to quit.

References and further reading:

1. Thomas Latimer Cancer Foundation: Cancer Facts
2. American Cancer Society: How common is lung cancer
3. Medical News Today: Cancer facts, causes, symptoms, and research
4. Chemo.net: Lung Cancer

Lung cancer rates on the decline

One of the hospitals I did my clinicals in back in the mid 1990s had a cancer clinic, and when I had to give breathing treatments to those patients, there was kind of a gloomy feel. Most of those patients knew they had terminal cancer.

Yet, according to this post from Reuters, lung cancers and other cancers, such as colon cancer, are on the decline according to statistics accumulated from the American Cancer Society. The report noted the decline was due to fewer people smoking, better treatment, and early intervention.

The report noted that "Death rates for all cancer types fell by 2 percent a year from 2001 to 2006 among men and 1.5 percent per year from 2002 to 2006 in women."

Likewise, " lung cancer rates have fallen in men by 1.8 percent each year since 1991 and finally started leveling off among women... The overall U.S. death rate from cancer in 2007 was 178.4 per 100,000 people, a 1.3 percent drop from 2006, when the rate was 180.7 per 100,000."

According to one expert from the American Cancer Society, "In that time, mortality rates have decreased by 21 percent among men and by 12 percent among women, due primarily to declines in smoking, better treatments, and earlier detection of cancer."

Once again it should be known that smoking is the #1 cause of lung cancer, with nearly 90% of those getting lung cancer current or former smokers. As you can see from the graphic, lung cancer was nearly non-existent in America until people started smoking. About 20 years after people started smoking, the lung cancer rate climbed.

Thus, as people quit smoking, perhaps some with the help of us RTs and our smoking cessation education, and perhaps due to rising cigarette prices, and laws that continue to phase out cigarettes in public places, the lung cancer rate should continue to decline

In a related article from therecord.com, a study done in Canada showed that people are less sympathetic of people with lung cancer due to the link between smoking and lung cancer. The study showed that 1 in 4 Canadians noted little to no sympathy.

I suppose since smoking is no longer the "in-thing", and no longer "cool," many people who don't smoke (a growing number) believe that those who smoke got what they deserved. What they don't realize is that in the 1950s and 1960s when our parent's generation was growing up, and smoking was cool, there was no wisdom as to the dangers of smoking.

Actually, the wisdom was there, yet the powers that be didn't let this wisdom spread as the tobacco industry was a major profit maker for the American economy. So, in that sense, I think we ought to have sympathy for those with lung cancer as with any other victims of cancer.

One concern by lung cancer experts is that with so little sympathy for lung cancer patients, monies set aside for lung cancer research and treatment won't be as much as for other diseases. Although the American study mentioned above may show Americans are a little more sympathetic to smokers than Canadians, as U.S. lung cancer trends are on the decline.