The release by the National Cancer Institute (NCI) of the results of its eight year National Lung Screening Trial (NLST) is an exciting research development for those at risk for lung cancer and early detection. While a success story in many respects it is also at this juncture limited in its scope and application. Much more needs to be done not only with interpreting the NLST but developing other safe, low cost methods of early detection.
The NLST enrolled 53,000 current and former smokers between the ages of 55 and 74. The initial results concluded that yearly CT scans reduced the mortality rate of lung cancer by 20 percent. The NCI noted that it was the first time there has been “clear evidence of a significant reduction in lung cancer mortality with a screening test in a randomized controlled trial.” 20 percent is a significant number when weighed against the reality of yearly deaths of men and women from lung cancer in excess of 150,000.
U.S. Preventive Services Task Force (USPSTF) Recommendation
The U.S. Preventive Services Task Force (USPSTF) makes recommendations about the effectiveness of specific preventive care services for patients without related signs or symptoms.
It bases its recommendations on the evidence of both the benefits and harms of the service and an assessment of the balance. The USPSTF does not consider the costs of providing a service in this assessment.
The USPSTF recognizes that clinical decisions involve more considerations than evidence alone. Clinicians should understand the evidence but individualize decision making to the specific patient or situation. Similarly, the USPSTF notes that policy and coverage decisions involve considerations in addition to the evidence of clinical benefits and harms.
As a result of the National Lung Screening Trial, the USPSTF recommends annual screening for lung cancer with low-dose computed tomography (LDCT) in adults aged 55 to 80 years who have a 30 pack-year smoking history and currently smoke or have quit within the past 15 years. Screening should be discontinued once a person has not smoked for 15 years or develops a health problem that substantially limits life expectancy or the ability or willingness to have curative lung surgery.
NLST is a significant step in the right direction, not simply because of the results but for the fact that it showcases the importance of lung cancer research and that great strides are possible when funding is made available for lung cancer research.
While the NLST at present is the only definitive and positive research for the early detection of lung cancer there are other promising and interesting research programs underway. These include a blood test that detects a protein that could be used to detect lung cancer; the use of so-called sniffer dogs; the use of cells from the interior of the nose; breathalyzers; and, sputum tests to name a few.