No, according to the latest and one of the best-designed studies on the subject, which is being released today by the journal Cancer.
Researchers from the University of Pennsylvania School of Medicine looked at data from two studies involving 1,093 patients with head and neck cancer. After 10 years, they found that neither a positive nor a negative emotional state had any effect on cancer survival or progression of disease.
"We left no stone unturned. If there had been a link between emotional state and survival, we would have found it because the study was so large and because all patients had advanced cancer and received very similar treatment," said lead author Dr. James Coyne, a professor of psychiatry.
The study comes on the heels of another important finding announced in July, that group therapy does not extend survival among breast cancer patients, as many people had hoped.
Both studies are important because they further debunk a popular but false belief that the mind can conquer cancer, said psychologist and medical sociologist Barrie Cassileth, chief of the integrative medicine department at Memorial Sloan-Kettering Cancer Center in New York.
"It's a popular mythology, particularly in the United States, that if you try hard enough, you can overcome anything, that if you really will it and have the right emotional and mental perspective on life, you can conquer your cancer," said Cassileth.
"It's a completely false notion, and it's very destructive because it imposes on people with cancer yet another burden - the burden of guilt." While stress and emotional state can influence some cardiac risk, "it's not the same thing when it comes to a genetic abnormality, which is what cancer is," she said.
Previous studies suggesting that better mental health was linked to better cancer survival were methodologically flawed, said the University of Pennsylvania authors, adding that the idea that there is a link "has been remarkably resilient in the face of contrary data."
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