Can stress cause cancer? The response from our expert oncologist

in collaboration with

Ivan Pourmir (medical oncologist)

Can emotional shock and the resulting stress cause cancer a few months or years later? The preconceived idea, rather widespread, was mentioned again while the announcement of the cancer of King Charles III caused a lot of noise in the media. On Monday, host Stéphane Bern, specialist in crowned heads, put forward the same hypothesis: “We know that cancers can develop thanks to emotional shocks. And, with Harry, the ordeal was very painful.” But is he telling the truth? What does science say? We asked the question to Dr. Ivan Pourmir, oncologist and immunology researcher, member of our expert committee.

A causal link that is very difficult to explore scientifically

If since then, the mention, “It has never been scientifically demonstrated that a psychological or emotional shock could cause or promote cancer. was affixed as a precaution to the article of the Parisian, our expert qualifies this statement a little. “At the scientific level, let us say above all that today we have little reliable epidemiological data on this subject, allowing us to conclude that there is a significant link or not.

And for good reason, exploring the effect of stress on the occurrence of cancer from an epidemiological point of view would be extremely complicated. “Observational studies are needed that would require quantifying the state of stress of somebody. But in what way? There are so many ways, reasons to stress or experience stress… We would then have to quantify this in a reproducible and relevant way, to give a stress score and see how people evolve, see if they develop more or less stress. cancer according to their stress, prospectively or retrospectively. There are also so many other factors that can come into play (such as exposure to carcinogens, etc.) with or without stress, that the bias would be enormous. explains our expert.

But an effect on the immune system plausible

In terms of scientific evidence, the causal link is therefore difficult to quantify. On the other hand, in terms of hypotheses, the mechanism between the psyche and the occurrence of cancer is an area of ​​particular interest to researchers.

“There are two possibilities. On the one hand, it is possible to envisage that our nervous system produces hormones during periods of stress, and that these substances have an effect on the cancerization of cells. But as the researcher mentions, this hypothesis would take many years to produce an effect that is difficult to prove. “This does not allow us to say that stress is the cause of a cancer discovered 6 months later.”

The other plausible mechanism is that the relationship between stress, or a negative psychological state (such as depression, trauma, bereavement, etc.) and cancer, occurs through the immune system. “What we are beginning to characterize in a solid way is that our psychological state and our mind have an influence on our immune system and its ability to perform certain functions, including those of fighting infections, monitoring the body or suppressing cancer cells as much as possible. specifies our expert.

Let’s imagine that your immune system manages to contain a cancer in the microscopic phase, a sudden life event causing immunosuppression could encourage the cancer to advance and make it detectable. “But it’s a possibility, not a certainty.” tempers Dr. Pourmir.

Use this link to reverse the effect

The possibility of an existing link between mental health and the development of cancer is, however, not so negative. “Conversely, if this relationship exists, this means that there would then be opportunities to intervene on the mind, in a non-drug way, capable of amplifying existing treatments and healing. I would be interested to see what meditation, hypnosis or things of this order can do to people’s psyches and to what extent it would modulate their immune system and favor the action of treatments like immunotherapies. Moving forward in this direction would be real progress.”

Regardless, one point remains essential for our expert: there is no point in making people feel guilty because something happened to them in the past, or because they were unable to remain positive in the face of a difficulty or during their cancer. “If you start to feel guilty as soon as you are not positive, it becomes complicated to live with, and it’s a vicious circle” concludes the oncologist.

Slide: Misconceptions about cancer