Lung Cancer Screening: Guidelines for early detection of lung cancer in smokersPublished 8:31pm Saturday, February 16, 2013
Remember the old adage “an ounce of prevention is worth a pound of cure?” When it comes to cancer screening, we are headed in the direction of catching lung cancers earlier, giving smokers some hope. An estimated 45.3 million people, or 19.3 percent of all adults, in the United States smoke cigarettes. Cigarette smoking is more common among men (21.5 percent) than women (17.3 percent). By region, in 2010, smoking prevalence was highest in the Midwest (21.8 percent) and South (21.0 percent) and lowest in the West (15.9 percent).
Cigarette smoking is the leading cause of preventable death in the United States, accounting for approximately 443,000 deaths, or one of every five deaths, in the United States each year. In the past few years there has been increasing controversy as to whether continued smoking is due to nicotine addiction or the result of habitual behavior. We know that “never smokers” have the least risk of developing lung cancer. So if you do not smoke, count your blessings.
For current smokers who fall into high risk groups, it is now recommended that they undergo a special CT scan to look for signs of early lung cancer. These CT scans use lower doses of radiation to look for cancer cells. A lung cancer screening trial studied people aged 55 years to 74 years who had smoked at least one pack of cigarettes per day for 30 years or more (referred to as “30 pack years”). Heavy smokers who had quit smoking within the past 15 years were also studied. The trial used chest x-rays or low-dose CT scans (LDCT) scans to check for signs of lung cancer.
The CT scans were better than chest x-rays at finding early lung cancer. Screening with LDCT also decreased the risk of dying from lung cancer in current and former heavy smokers. The risk of dying from lung cancer was decreased by 20 percent in those screened using CT scans.
What are the benefits of being screened for lung cancer? The main benefit of screening is that it helps doctors find cancer early. In these cases it should be easier to treat and treatment may lower your chances of dying from lung cancer.
What are the drawbacks to being screened for lung cancer? The drawbacks include false positive results. This means that on the CT scan it looks like there is cancer when in reality there is no cancer but maybe only inflammation. This can lead to more tests and anxiety about the results. More tests may mean more radiation and this may lead to a need for a biopsy of the lung. A lung biopsy is a procedure to remove a small sample of lung tissue. This procedure can be painful and lead to problems such as bleeding or a collapsed lung.
Another drawback of lung cancer screening is that it exposes you to more radiation. All x-rays, including CT scans, expose you to some radiation. Although the radiation dose from the first screening CT scan is low, you would need to have a scan every year, so your exposure would add up. Plus, if you have an abnormal low dose CT, you could end up having full dose CT scans. Increasing doses of radiation from scans being done on a regular basis may lead to increasing your chances of developing certain cancers such as breast cancer.
Of note, exposure to second hand smoke was not a risk factor that would warrant CT screening. For previous smokers, those who had quit within the past 15 years or those with a 20 pack-year history (that is, a person who smoked one pack a day for 20 years, or who has smoked two packs a day for 10 years), with an additional risk factor (like diabetes, congestive heart failure, or emphysema) could be screened.
If you or a family member are at risk for lung cancer, speak to your doctor about the risks and benefits of being screened. It would be helpful to have this or a similar article with you at the time of your discussion. Do not be timid about asking these important questions.