February 03, 2023
In France, three screening programs are organized for eligible people, in order to detect the first signs of a possible tumour. They concern breast cancer, cervical cancer and colorectal cancer. Thanks to recent advances, lung cancer could soon join the list.
Breast, cervix, colon-rectum. These localizations of cancers are subject to screening organized by the public authorities, in order to “ detect the presence of a disease at an early stage in people who are a priori in good health and who do not yet show apparent symptoms”, details the High Authority for Health (HAS). They specifically target populations considered to be more at risk of developing the disease, to whom examinations are offered at regular intervals. Objective: to diagnose the disease as early as possible to treat it quickly or slow its progression.
It is not yet possible to detect all types of cancer. To consider screening, a certain number of criteria are necessary, recalls the HAS:
– The disease must be detectable early but progress slowly, with “a sufficiently long period between the moment when the disease is detectable and the appearance of the first symptoms, if we want to be able to carry out screening, confirm the diagnosis and institute an effective treatment” ;
– A suitable screening test must be available;
– Effective treatments must be able to be quickly proposed and implemented;
– The people most at risk of the disease must be easily identifiable;
– Screening should reduce mortality;
– Screening should have more advantages than disadvantages.
Benefit/risk
For breast, cervical and colorectal cancers, these criteria are met: this is why they can be the subject of organized screening. But this is not the case with prostate cancer, for example: “the benefit of screening for prostate cancer has not been clearly demonstrated: it is not certain that this screening will prevent deaths linked to (this disease)”, says Medicare. It has been proven that this type of cancer, whose evolution is difficult to predict, leads to overdiagnosis and overtreatment.
And lung cancer? Responsible for more than 45,000 new cases in 2018, it represents the third leading cause of cancer in France and the leading cause of death, with tobacco as the main culprit in 8 out of 10 cases. poor prognosis is not the subject of organized screening, this could soon change.
Pilot program
In February 2022, the Haute Autorité de Santé indeed recommended “the commitment of a pilot program” conducted by the National Cancer Institute (INCa), for the “screening for bronchopulmonary cancer by low-dose thoracic CT scan without injection in a population at high risk of this cancer”i.e. smokers and former smokers.
This test, also called a CT scan, reduces the “specific mortality” linked to this cancer, which is often diagnosed late, according to data from “systematic reviews, with or without meta-analysis, including international comparative clinical trials”. But before seeing lung cancer enter the list of cancers subject to organized screening, many elements must still be defined, such as the eligibility criteria for the target population or the screening methods.
Other studies are carried out in parallel to obtain the missing data, such as theCASCADE study initiated by the APHP, which specifically targets smokers and ex-smokers aged 50 to 74. In total, 2,400 women will be able to benefit from free screening over two years, in Paris, Béthune, Grenoble or Rennes.
To know : For people with particular risk factors (personal or family history), specific and individual monitoring is organized, most often at the request of the attending physician.