Story updated 3/11/2015
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Last year, the United States Preventive Services Task Force, an influential panel of national medical experts, recommended that older, longtime smokers be screened annually for lung cancer — the leading cancer killer in the United States, with almost 160,000 deaths yearly — for early detection. The recommendation was supported by the American Cancer Society and the American Lung Association. Now, the Centers for Medicare & Medicaid Services (CMS) has approved a proposal to cover the cost of lung cancer screening for a specific group of Medicare recipients ages 55-77 who had smoked for 30 pack years.
Lung cancer is rarely caught early enough to be effectively treated. The screenings would be done through low-dose computed tomography (CT) scans.
Oncologist Nathan Pennell, MD, PhD, answers questions about the screening recommendation.
Q: This seems like an obvious thing to do for longtime smokers. Why did it take so long for this recommendation?
Dr. Pennell: “You are right that the screening makes good sense. Why not look to see if you can find lung cancers when they are still at an early stage and curable, as opposed to waiting until patients develop a cough or other symptoms when the cancer is more likely to be incurable?
“The issue has been that up until now the best test hadn’t been defined. A lot of time and money went into testing chest x-rays in the 1970s for lung cancer screening, but x-rays weren’t sensitive enough to pick up cancers early enough and the end result was that screening didn’t save any lives.
“That changed when the National Lung Screening Trial showed that low-dose CT scans, which cover the entire lung and can pick up tiny tumors, can reduce deaths from lung cancer by 20 percent when done annually in high-risk people, that is, smokers.”
Q: Are there risks associated with the CT scans?
Dr. Pennell: “There is a small risk associated with the ionizing radiation from CT scans, but limiting the scans to older people ages 55-74 and using the least amount of radiation necessary — low dose CTs have only about 20 percent as much radiation as a regular CT— makes the risk very small. There is also the risk, however, that the CT may show a lung nodule that is not cancer, and some individuals will have to undergo additional testing.”
Q: How is lung cancer typically treated?
Dr. Pennell: “Treatment of lung cancer depends on how advanced it is when it is discovered, also known as the “Stage.” The goal of lung cancer screening is to identify lung cancers at an early stage, before they have spread outside the tumor itself. For stage I cancers which are localized to the lung alone, surgical removal of the tumor is the most effective treatment. If a patient has other medical issues that make surgery unsafe, then radiation is also very effective at curing early stage lung cancers.”
Q: The five-year survival rate for lung cancer has barely budged over the years. What is the benefit in terms of survival rate of screening and catching the lung cancer early?
Dr. Pennell: “It is true that the five-year survival for lung cancer is much the same today as it was in 1980 despite major advances in treatment. The reason behind this is that most lung cancers are diagnosed when they are either incurable or very unlikely to be cured. You can’t see or feel your lungs, so tumors can grow undetected for a long time before they cause problems a patient would notice, and by then it is often too late.
“However, early stage lung cancers are very curable. In one large lung cancer screening trial called the IELCAP, stage I lung cancer patients had about a 90 percent chance of being alive five years later. The problem then becomes how do we detect more lung cancers when the cure rate is 90 percent rather than 0 percent? That is the promise of screening, to reduce the number of patients dying from lung cancer — in the lung cancer screening trial it was by 20 percent — by finding them early.”
Q: Who specifically should get the annual screening?
Dr. Pennell: “The Lung Cancer Screening Trial included patients who were ages 55-74, had smoked for 30 pack years, and had not quit for more than 15 years. Thirty pack years means packs per day multiplied by the number of years you smoke, so a two pack-per-day smoker only needs 15 years, three pack-per-day 10 years, and so on.
“If you fall into this group, then the best thing you can do for yourself is to quit smoking! Your doctor can help you with this, and if you do enter a screening program, then smoking cessation will be a part of the process. You should also consider getting a low-dose CT scan once per year.
“We don’t recommend screening people who quit more than 15 years ago because their risk, while still higher than a person who never smoked, is quite low at that point.”
Q: What else do you feel is important for consumers to know?
Dr. Pennell: “For decades, the number of people dying from breast cancer, colon cancer, prostate cancer and cervical cancer has been dropping due to effective screening efforts. However, more Americans die from lung cancer every year than from all of these other cancers combined. For the first time, we have an effective method of screening for lung cancer and can greatly reduce the number of people who die from this horrible disease, so if you fit the criteria for high risk then take the steps to protect yourself and get screened!”
Non-smokers: Steer clear of secondhand smoke