More than 160,000 Americans die each year from lung cancer—more than breast, colon, and prostate cancers combined.
Eight out of 10 cases of lung cancer are due to smoking or an indirect exposure to tobacco smoke; the rest are a result of exposure to industrial chemicals such as asbestos, arsenic, and polycyclic hydrocarbons, or to natural radioactive gases like radon. Some have no known cause at all. Some studies show that women who smoke have a higher incidence of lung cancer as compared to men, and women also die at a greater rate from lung cancer than men.
While it’s clear that the longer you smoke, the greater your chances are of developing lung cancer, not all smokers develop lung cancer. This leads researchers to think that there may be an inherited component that influences whether or not smoking will cause lung cancer. The majority of lung cancer cases occur in people aged 60 and older, though by the time it’s diagnosed at that age, the cancer has been under development for decades.
The symptoms of lung cancer vary greatly, from difficulty breathing to coughing up of blood to a loss of appetite and weight loss to fatigue. But some lung cancers show no symptoms at all until they’re very advanced, by which time it has usually spread to other parts of the body.
Lungs cancers are either of the small-cell type or the non-small-cell type. Small-cell lung cancer is responsible for 15 percent of all cases and is most prevalent among smokers. It’s an aggressive cancer that spreads rapidly and responds best to chemotherapy.
The other three types of lung cancer are of the non-small-cell variety. The most common of these is adenocarcinoma, which accounts for 40 percent of lung cancers, is most frequently found in women, and has been linked to low-tar cigarette smoking. Squamous cell carcinoma is slow-growing, causes 30 percent of lung cancers, and usually responds well to surgery.
The third type, large-cell carcinoma, is the least common type of lung cancer, responsible for only about 15 percent of the cases; surgery is the primary treatment for this type of lung cancer.
Many lung cancers are diagnosed at the time of an incidental chest X-ray. The lung cancer must usually be quite advanced to show up on an X-ray. Otherwise, the primary method for diagnosing lung cancer is through a bronchoscopy, which involves inserting a tube inside the windpipe all the way down to the lung chambers, where a doctor can either see or biopsy a specific tissue to make a diagnosis. Bones scans, CAT scans, and MRIs are used to determine the extent of the lung cancer—whether it has spread to other parts of the body, like the liver, the brain, or the bones.
A Fire Without Smoke
Everyone was saddened by the death of Dana Reeve in 2006. Who could not admire the way she stood by her husband Christopher “Superman” Reeve through the ordeal of his paralysis? Dana Reeve died of lung cancer at the age of 44. She had never smoked in her life. Many people wondered how this could possibly happen, believing that lung cancer occurs only in people who have been long-time smokers.
But people can get lung cancer even if they do not smoke. Ten to 15 percent of people who develop lung cancer have never smoked, in fact. No one knows why, though the cause of the lung cancer in these individuals is thought to be a combination of genetic and environmental factors.
Certainly, your risk of developing a nonsmoking-related lung cancer is greater if you have family members who have had lung cancer. And, notably, these nonsmoking-related lung cancers are more often found in women than in men. No one knows why.
Once lung cancer has been diagnosed, several treatment options are available, including surgery, chemotherapy, and radiation, depending upon the stage and type of the cancer. All of these treatments have their side effects, including fatigue, hair loss, diarrhea, nausea, vomiting, and anemia.
Lung cancer survival depends on the cell type, the size of the tumor, the location of the tumor, and whether or not it has spread. More than half of all lung cancer patients die within one year of being diagnosed. Only about one in seven are still alive five years after diagnosis.
Currently there is no routine screening for lung cancer. But if lung cancer is so common, and if diagnosis usually occurs too late for treatments to make a significant difference, why is the medical community not more aggressive at screening?
There is a national initiative to begin just such a screening program. The first step would involve screening people with risk factors for lung cancer. Is the person a smoker? Is there lung cancer in that person’s family?
The next step, still unresolved, involves the best screening tool for the job. Should it be a CAT scan? A bronschoscopy? Some other method? Which one is more sensitive? Which one is more cost-effective?
Someday, I hope in the near future, we will have national screening for lung cancer. I think it will make a difference.
Click here to check out Dr. Manny's book The Check List (Harper Collins, 2007), from which this article was excerpted.
Dr. Manny Alvarez is the managing editor of health news at FOXNews.com, and is a regular medical contributor on the FOX News Channel. He is chairman of the Department of Obstetrics and Gynecology and Reproductive Science at Hackensack University Medical Center in New Jersey. Additionally, Alvarez is Adjunct Professor of Obstetrics and Gynecology at New York University School of Medicine in New York City.