More than one in two non-smoking lung cancer would be linked to air pollution: News

Atmospheric pollution in particular in Southeast Asia, appears as one of the factors of the predominance of adenocarcinoma, which has become the most common type of lung cancer in the world, especially in non-smokers, according to a Study published Tuesday.
With around 2.5 million people diagnosed in 2022, lung cancer remains the most common in the world. If the majority of cases remain diagnosed in men (1.6 million), the gap with women tends to be reduced (910,000 cases), notes this study published in the journal Lancet Respiratory Medicine on the occasion of the day global against cancer.
Among the four main subtypes of lung cancer, adenocarcinoma has become predominant in women in 185 countries of the world and, in men, in 150 countries (apart from those of Eastern Europe and Asia the West), according to this analysis of data from the Cancer Agency for the World Health Organization, CIRC.
In 2022, he thus represented almost one case of lung cancer in two in men (45.6%, or 717,211 cases), and six out of ten (59.7%, or 541,971 cases) in women, against respectively 39% and 57.1% estimated in 2020.
He thus arrives far ahead of the other three types: epidermoid carcinoma (29.4%), small cell carcinoma (11.5%), closely linked to tobacco consumption, and large cell carcinoma (6.5 %), rarer.
Changes in the manufacture of cigarettes and in smoking practices since the 1950s have been able to play in this evolution.
But the prevalence of smoking continues to decrease in many countries, while the proportion of lung cancers in non-smokers has increased, observe the researchers.
Lung cancer in non-smokers has even become “the fifth cause of mortality related to cancer worldwide, manifesting itself almost exclusively in the form of adenocarcinoma and most often in women and Asian populations”, underlines the study.
– fine particles –
After a series of analyzes, it concludes that “air pollution can be considered as an important factor which partially explains the growing predominance of adenocarcinoma -thequel represents 53 to 70% of cases of lung cancer in non -non -Fumers in the world “.
Among the adenocarcinomas diagnosed in 2022, nearly 200,000 were thus associated with ambient air pollution by fine particles: 114,486 cases in men and 80,378 cases in women, according to their estimate.
Since 2019, around 99% of the world’s population has lived in areas that do not meet the WHO air quality criteria, according to organizational figures.
In “some rapidly transitional economics such as China, where a constant increase in fine particles concentrations in air pollution has been observed, exposure to fuels used for domestic heating and cuisine could explain the occurrence of cancers lungs in women, “according to the study.
Indeed, the implications of adenocarcinomas attributable to the highest air pollution have been noted in East Asia, especially in China.
If the authors call to interpret their results with prudence, taking into account certain methodological limits and the variable availability of data from one country to another, they believe that their study highlights the need for continuous monitoring of evolution the risk of lung cancer.
Especially since if the incidence of lung cancer in men have decreased in most countries for 30 to 40 years, they have increased in women.
“These divergent tendencies according to sex” must guide “specialists in cancer prevention and political decision -makers” towards “strategies to fight tobacco and air pollution adapted to high -risk populations”, estimates the researcher of CIRC Freddie Bray, who conducted the study.
The authors still argue for the implementation of cancer registers and for exploring the role of air pollution, where smoking is not considered the main cause of this disease.
Posted on February 4 at 3:46 p.m., AFP