Lung cancer is due to exposure to fine particles PM2.5, those resulting in particular from exhaust gases or waste incinerators. If this link had been established for a long time, British scientists have understood how air pollution triggers cancer in the human body and presented their results on Saturday September 10 at the European Cancer Congress, which is being held in Paris.
This cancer develops around a gene present in the human body, more precisely a mutation of the EGFR gene, deciphers Dr. Suzette Delaloge, oncologist at the Gustave Roussy Anti-Cancer Institute in Villejuif: “What they demonstrate is that in normal tissue with an EGFR mutation that the intervention of small particles of the pollutant PM 2.5 will create a micro-environment, an inflammation that will promote cancer. Conceptually , it’s a pretty, very clear demonstration and for which we still had little at this level.”
If the mechanisms are now known, it is interesting to note that not everyone has this mutated EGFR gene. “The older we get, the more mutations we have and we have a lot of them in fact. EGFR mutations are present in 30% of normal lungs, if we do biopsies”explains Dr. Suzette Delaloge. “It’s a bit of a coincidence that at some point you will have this mutation and you will be exposed to pollutants.”
“So for example if you never have an EGFR mutation in your normal tissues, you don’t develop pollution-related cancers, even when exposed.”
Dr Suzette Delaloge, oncologistat franceinfo
This discovery opens up avenues for research on pollution-related lung cancer. “We should be able in the coming years to intercept these cancers much betteradds Dr Suzette Delaloge. Intercepting means both detecting them earlier and treating them. That is to say that in fact, we will have drugs that will prevent the action of pollutants on the lung and potentially prevent the occurrence of cancer.
The study does not say how long you need to have been exposed to fine particle pollution, or in what proportion. But in Asia, where these lung cancers frequently develop in non-smokers who are very exposed to pollution, they generally start in patients who are just under 50 years old.