Lung cancer: Organized screening would reduce mortality by at least 25%
Screening for lung cancer by chest scan in people at risk could reduce the mortality of this disease by 25% in men and 40-60% in women, according to a Dutch-Belgian study. These results were reported in early September at the annual conference of the International Association for the Study of Lung Cancer. As early as 2011, a U.S. study called NLST had concluded that there was a 20% drop in mortality through screening. As a result, many specialists, including those of the French-speaking Intergroup of Thoracic Cancer or the Oncology Group of the French Language Pneumology Society, are in favour of systematic screening for individuals at risk, such as this is already the case in the United States.
A small proportion of false positives
In France, however, such a measure is not expected to happen for several years. At issue is a 2016 high health authority (HAS) decision, which focuses on the risk of generating false positives and the danger of radiation. Two remarks that do not pass for Professor Sébastien Couraud, oncologist and pneumologist at the civil hospices of Lyon, favorable to screening. He explains that the 2011 U.S. study had its limitations: after a CT scan, the test was either positive or negative. So there were 97% false positives. "Nevertheless, the aim was not to implement this technique, but to show that it was possible," notes the pulmonologist. The Dutch-Belgian study is much more precise, according to him: "If the nodules are intermediate in size, we see how they evolve and we re-scan three months later. If it has evolved suspiciously, the screening is positive." A very important nuance, since it greatly reduces the number of false positives.
As for the argument of irradiation, again, many pneumologists and oncologists are dubious. "Of course there are. However, the scanners in the NLST study, which lasted from 2000 to 2010, are not the same as they are now. At the time, a CT scan was, on average, the equivalent of six months of natural irradiation. Today, this dose can be reduced by two to three times. Soon, it will be further reduced and equivalent to that received during a mammogram, for example," sums up the practitioner. There is still the risk of radio-induced cancer. If the pulmonologist acknowledges that there is no such thing as zero risk, for him, the argument is quite wobbly. Indeed, such a cancer takes 10 to 30 years to develop, and here, the individuals concerned are around 60 years old. The risk is therefore 'acceptable', especially since it is greatly reduced after 50 years.
Detecting cancers at an earlier stage
Today, for Professor Couraud, the evidence of the effectiveness and beneficial effects of systematic screening of at-risk individuals is therefore more than sufficient to start setting up experiments, as is the case in Great Britain, Germany or Italy. Because in France, for the moment, only an operation of this kind is under way. Dr. Olivier Leleu, in the Somme, conducts a cohort study of 1,200 people. However, after the negative opinion of the HAS, the Regional Health Agency (ARS) stopped subsidizing the research. The study continues, however, and the people involved show a real enthusiasm. The participation rate is estimated at 78% on the at-risk population of the Somme. For Professor Couraud, this is proof that heavy smokers are ready to get tested.
A small proportion of false positives
In France, however, such a measure is not expected to happen for several years. At issue is a 2016 high health authority (HAS) decision, which focuses on the risk of generating false positives and the danger of radiation. Two remarks that do not pass for Professor Sébastien Couraud, oncologist and pneumologist at the civil hospices of Lyon, favorable to screening. He explains that the 2011 U.S. study had its limitations: after a CT scan, the test was either positive or negative. So there were 97% false positives. "Nevertheless, the aim was not to implement this technique, but to show that it was possible," notes the pulmonologist. The Dutch-Belgian study is much more precise, according to him: "If the nodules are intermediate in size, we see how they evolve and we re-scan three months later. If it has evolved suspiciously, the screening is positive." A very important nuance, since it greatly reduces the number of false positives.
As for the argument of irradiation, again, many pneumologists and oncologists are dubious. "Of course there are. However, the scanners in the NLST study, which lasted from 2000 to 2010, are not the same as they are now. At the time, a CT scan was, on average, the equivalent of six months of natural irradiation. Today, this dose can be reduced by two to three times. Soon, it will be further reduced and equivalent to that received during a mammogram, for example," sums up the practitioner. There is still the risk of radio-induced cancer. If the pulmonologist acknowledges that there is no such thing as zero risk, for him, the argument is quite wobbly. Indeed, such a cancer takes 10 to 30 years to develop, and here, the individuals concerned are around 60 years old. The risk is therefore 'acceptable', especially since it is greatly reduced after 50 years.
Detecting cancers at an earlier stage
Today, for Professor Couraud, the evidence of the effectiveness and beneficial effects of systematic screening of at-risk individuals is therefore more than sufficient to start setting up experiments, as is the case in Great Britain, Germany or Italy. Because in France, for the moment, only an operation of this kind is under way. Dr. Olivier Leleu, in the Somme, conducts a cohort study of 1,200 people. However, after the negative opinion of the HAS, the Regional Health Agency (ARS) stopped subsidizing the research. The study continues, however, and the people involved show a real enthusiasm. The participation rate is estimated at 78% on the at-risk population of the Somme. For Professor Couraud, this is proof that heavy smokers are ready to get tested.