Somewhere between 40 and 70 percent of all people with lung cancer will also have COPD. If you have COPD, your risk of developing lung cancer — especially squamous cell carcinoma — is much higher. The risk quintuples if you're a smoker with COPD. What's more, people already diagnosed with chronic obstructive pulmonary disease have a poorer prognosis than others if they do develop lung cancer, too.
Smoking: A risk factor COPD and lung cancer share
Smoking cigarettes is a leading cause of both COPD and lung cancer. Cigarettes are full of free radicals like reactive nitrogen and oxygen species, which wreak havoc on your cells and cause oxidative stress. This, in turn, damages DNA and promotes cancer. Some stats that should concern you are:
- Smokers with lung cancer are six times more likely to have COPD than those who don't (yet) have lung cancer.
- In real terms, fully half of smokers who have just been diagnosed with lung cancer also have COPD.
- If you already have COPD, still smoke, and your lung function is severely impaired, your risk of developing lung cancer goes through the roof.
Chronic inflammation is common to both COPD and lung cancer
Chronic inflammation eventually sets in after your lungs are exposed to irritants, dusts, or pollutants over and over again. Smoking is, of course, a primary way to get there. COPD can result. Inflammation also plays an important role in the development of cancer. In the case of lung cancer, pre-existing COPD and its related inflammation may lead to a cycle of cell damage and cell repair that can trigger proteins that contribute to the growth of cancerous cells.
Hypoxia, or insufficient oxygen, may contribute to lung cancer
The limited airflow that results from chronic obstructive pulmonary disease can, over time, lead to hypoxia — a fancy term for "not getting enough oxygen". Lungs that don't get enough oxygen also become an environment in which cancerous cells can proliferate, so this consequence of COPD is one way in which the disease increases your risk of lung cancer.
Shortened telomeres and what they mean
Without getting too scientific, telomeres are important parts found at the end of DNA strands. They "cap" and protect chromosomes, but can become shortened over time. This happens as we age, but the process can speed up depending on the things we're exposed to. The length of telomeres says something about your physical age, then, rather than your age in years. We all know smoking leads to premature aging, and that includes telomere shortening.
Do COPD and lung cancer run in families?
Studies have indeed shown that people with a family history of either lung cancer or COPD are more vulnerable to developing these respective conditions themselves. This isn't just because smoking can also "run in families" as it were, but due to an actual genetic susceptibility.
How does being female affect your risk of lung cancer and COPD?
Female sex hormones like estradiol impact, according to research, the way in which smoking impacts a woman's lungs — leading to higher levels of inflammation than seen in men, though this also depends on the stage of the menstrual cycle a woman of reproductive age is in. Estrogen further boosts the metabolism of cigarette smoke and taking estrogen replacement therapy adds to the risk of lung cancer even in women who don't smoke.
Lung cancer and COPD: When to sound the alarm bells
A diagnosis of COPD should automatically mean closer monitoring for signs of lung cancer, but patients can play an important role in this by seeing their doctor as soon as they notice something "off". Like COPD, lung cancer can cause shortness of breath and coughs, but a few symptoms should get your attention. These can indicate that you're not just dealing with COPD any more, and may also have lung cancer.
- Chest pain that strikes when you're not coughing.
- Coughing up blood, or finding that your phlegm contains blood.
- Fatigue.
- Unexplained and involuntary rapid weight loss.
- A lack of appetite.
- A hoarse voice.
See your doctor immediately if you think you have recognized potential signs of lung cancer. They should take your concerns very seriously, and order tests after conducting a physical exam, listening to your symptoms, and familiarizing themselves with your medical history. These diagnostic tests include:
- X-rays of the heart and lungs
- A CT scan of your lungs
- A sputum cytology, which looks for lung cancer cells in your mucus
- A bronchoscopy to get a closer look at your airways
- A biopsy
Once a person receives a lung cancer diagnosis, the stage of the cancer will first be determined. The treatment plan will depend on this, and chemotherapy, radiation, and surgery are among the options. COPD management plans like pulmonary rehab, and stopping smoking, should also remain high on the agenda.
Sources & Links
- Raviv, S., Hawkins, K. A., DeCamp, M. M., & Kalhan, R. (2011). Lung Cancer in Chronic Obstructive Pulmonary Disease. American Journal of Respiratory and Critical Care Medicine, 183(9), 1138–1146.
- Barnes PJ, Adcock IM. Chronic obstructive pulmonary disease and lung cancer: a lethal association. Am J Respir Crit Care Med. 2011, 184(8):866-867.
- Turner MC,Chen Y, Krewski D, Calle EE, Thun MJ. Chronic obstructive pulmonary disease is associated with lung cancer mortality in a prospective study of never smokers. Am J Respir Crit Care Med. 2007, 176(3):285-290.
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