- In France, lung cancer accounts for 15% of all new cancer cases.
- On average, people develop lung cancer around age 66.
In France, 46,363 new cases of lung cancer were diagnosed in 2018, according to the Institut Curie. In humans, this cancer is the deadliest, with 23,000 deaths per year. In women, there are about 10,000 each year, making it the second deadliest, behind breast cancer. Among the risk factors for lung cancer, one of the most important remains smoking. But it is still surprising to note that some heavy smokers, who consume more than one packet a day, do not develop this pathology and will never suffer from it. Why ?
Lung cells that do not mutate
Researchers have looked into exactly this question. According to them, if some heavy smokers do not develop this cancer, it is precisely thanks to the cells present in their lungs and more precisely to their ability not to mutate. Their work has been published in the journal Nature Genetics.
“These lung cells survive for years, even decades, and can therefore accumulate mutations with age and smoking. Of all the types of lung cells, they (those in the lung) are among the most susceptible to becoming cancerous” and yet “the heaviest tobacco users did not necessarily have the highest mutation rate”, explained to the media Science Alert, Simon Spivack, epidemiologist and pulmonologist at the Albert Einstein College of Medicine.
“Highly effective systems to detoxify cigarette smoke”
According to the authors, some smokers escape lung cancer because their body manages to suppress the accumulation of these mutations. “This stabilization of mutations could come from the fact that these people have very efficient systems for detoxifying cigarette smoke”the authors said.
Cancer develops in the body when mutations turn into tumours. Thus, the scientists estimated that the evolution of the mutation into a tumor comes from the capacity or the incapacity of the organism to repair the DNA which has been damaged by the tobacco.
“We now want to develop new tests that can measure a person’s ability to repair or detoxify DNA. This could offer a new way to assess lung cancer risk.”concluded Jan Vijg, geneticist at the Albert Einstein College of Medicine.