This article first appeared in the St. Louis Beacon: October 2, 2008 - Paul Newman, screen legend, racing enthusiast, philanthropist extraordinaire and dedicated family man, died last week. The icon, an ex-smoker, had reportedly been battling lung cancer, although he had kicked the tobacco habit many years ago.
Lung cancer is one of the most commonly diagnosed cancers, after skin (men and women), prostate (men) and breast (women), and it remains the leading cause of cancer death among both men and women, according to the Centers for Disease Control and Prevention. Smoking is the cause of close to 90 percent of lung cancer cases and although quitting does help, the risk of lung cancer is never eliminated for those with any history of the tobacco habit.
At Risk
But it isn't always cigarettes that lead to the disease. "A significant number of those with lung cancer have never smoked," said Dr. Keith Naunheim, chief of cardiothoracic surgery at Saint Louis University Hospital. One of every six of those diagnosed with lung cancer has never been smokers.
Among non-smokers who develop lung cancer, men have a higher death rate than women but the rates over time have not appeared to increase, according to research published online September 9 in PLoS Medicine. African-Americans and Asians living in Korea and Japan also had higher lung cancer mortality rates compared to those of European ancestry, the report indicated.
"The incidence of lung cancer among lifelong non-smokers falls within the National Cancer Institute's definition of a 'rare' cancer (fewer than 40,000 cases per year, age-standardized incidence rate less than 15 per 100,000)," the authors wrote.
Other risk factors include exposure to radon and asbestos. "In Missouri, there are areas of increased radon gas given off from the soil," Naunheim said. "There are radon detection kits to check for this."
Then, there is the question of secondhand smoke. "I think it is potentially harmful," Naunheim said, "but probably does not account for the large number of people with lung cancer. But it can cause symptoms in some people exposed to it, especially asthmatics or those with end stage lung disease."
In the Shadows
What can be especially troublesome about lung cancer is that symptoms very often do not occur until the disease is in far more advanced, and far less treatable, stages. Symptoms, when present, may include chronic cough, cough with production of blood, shortness of breath, chest pain, wheezing or weight loss. "Once there are signs, it is often so advanced it is beyond cure," Naunheim said.
Treatment largely depends on when the disease is diagnosed. "Forty to fifty percent of patients will come in with tumors that have already spread to an incurable stage, having spread beyond the lungs to sites including the liver, adrenal glands, bones, or the brain," Naunheim said. "When it spreads in this fashion, it is considered stage 4 disease, and is virtually incurable, although we can still treat them as far as improving quality of life."
The other 50 percent of cases, where the cancer is still confined to the lung, is considered stage 1 or stage 2 disease, according to Naunheim. "We can treat this aggressively," he said. "There's a good chance of cure, up to and around 70 percent."
Earlier Diagnosis
Patients can undergo screening for lung cancer, but it "has not proven to be useful," said Dr. Ramaswamy Govindan, oncologist at the Siteman Cancer Center at Barnes-Jewish Hospital and Washington University School of Medicine.
Naunheim agrees, saying that while screening has shown to improve rates of earlier diagnosis of tumors within the lung, it hasn't decreased the risk of death. He noted there are two on-going trials looking specifically at the question of screening in high risk (older than 50 with significant smoking history) patients to determine if there are fewer lung cancer deaths.
Though there is likely very little harm from an annual chest x-ray, the radiation risk from CT screening can really add up. "Routine screening with chest x-rays is not very useful," Govindan said. "And routine CT scans for lung cancer screening is not advisable either," both due to the high radiation levels that build up, as well as the risk of finding unrelated and inconsequential "false positives." These findings can include scar tissue from previous infections and can lead to much more costly testing and unnecessary anxiety for the patient.
Other screening tools may be on the horizon. A blood test screening for antibodies to certain agents (antigens) helping diagnose lung cancer before symptoms become evident may be possible, according to research published online Sept. 15 in the Journal of Clinical Oncology.
Bottom Line
Many lung cancers can be prevented. "Stop smoking, exercise more and eat less," advises Govindan. "And see your doctor regularly, keeping up to date with all your scheduled health maintenance exams and tests."
Dr. Cindy Haines is managing editor of Healthday-Physician's Briefing and president of Haines Medical Communications Inc., a full-service medical communications and consulting firm. As a board-certified family physician, Haines is well-versed in all areas of health care, with particular interest in fitness, nutrition, and psychological health.