November is Lung Cancer Awareness Month.
I recognized this important event by interviewing North Bay Medical Center hematologist-oncologist Jonathan Lopez. The event was a public access television show titled “Health Focus with Dr Scott,” which emphasizes health care prevention.
We air our shows on public access stations in Northern California.
Hosting this show has been a learning experience for me, as we seek to interview experts in various fields.
Dr. Lopez, known as “JD” to his friends, served nearly three decades on active duty with the Air Force, transitioning from enlisted serviceman to commissioned officer. Along the way, he attended the Uniformed Services University of the Health Sciences.
I was once an assistant professor of that institution. I was tasked with training students at our military hospital in San Antonio.
Many people are unaware of Uniformed Services University of the Health Sciences, which also educates nurses and scientists. The home campus lies in Bethesda, Maryland.
Later, Dr. Lopez became a sub-specialist in cancer diagnosis and treatment.
We discussed the lag time between exposure to carcinogens, and the development of cancer.
For example, smoking rates in our nation peaked in 1965, a year after Surgeon General Luther Terry released his seminal report attesting that cigarettes cause lung cancer.
The lung cancer rate peaked in 1995, a generation later.
In a similar manner, although we did not discuss this, the sun exposure we experience now, at any age, may cause skin cancer decades later.
Cancer deaths are declining as smoking rates become lower. Heart disease is also declining at an even faster rate.
Consequently, we see cancer emerging as a number one cause of death in nearly half of our states.
To a casual observer, these disparate observations are hard to sort out. In a sense, by avoiding a heart attack, we live long enough to be susceptible to more cancers.
In the case of lung cancer, 85 percent of cases are associated with active smoking, but those figures vary.
Non-smoking women are particularly vulnerable to lung cancer.
Why is that?
As Dr. Lopez eloquently explained, many habits that are troublesome to spouses, such as drug use, abate upon marriage, for various psychosocial reasons. Smoking, by contrast, may be tolerated by spouses.
Women, who smoke less frequently to begin with, may therefore be exposed disproportionately to secondhand smoke upon entering marriage. Although tobacco smoke contains more than 70 carcinogens, Dr. Lopez explained that the non-inhaled “side-stream” smoke from a cigarette is particularly toxic. The “side-stream” exposures alone may cause malignancies.
The scientific consensus on the effects of “vaping” is still developing, but Dr. Lopez did express concern about this phenomenon, which may be a gateway to smoking or to other addictions.
We discussed environmental contaminants that are linked to lung cancer. These include air pollution. Distance running in a polluted urban area may expose a would-be athlete to the equivalent of a cigarette, or two.
Exposure to radon gas, asbestos or other pollutants is also of concern. Genetic markers for lung cancer are being explored. Unfortunately, the kind of solid genetic markers that we see for breast cancer or ovarian cancer have yet to be identified.
With respect to screening for lung cancer, Dr. Lopez explained that the lung is a porous organ by its nature. Consequently, lung tumors may expand considerably before causing the classic symptoms of lung cancer, including pain, coughing up blood or weight loss.
That is why high-resolution CT scans are being explored, particularly for at-risk patient populations. More research is needed.
How can we prevent lung cancer? Dr. Lopez was unequivocal: “Don’t smoke. If you do smoke, quit.”
Surgeon General Terry, upon release of his 1964 report “Smoking and Health,” immediately jettisoned his own cigarette habit.
Scott T. Anderson, M.D., Ph.D. (email email@example.com), is a clinical professor at the University of California, Davis Medical School. This column is informational and does not constitute medical advice.
Scott T. Anderson, MD, PhD, is a clinical professor at the University of California, Davis, Medical School.