The problem with people like the author is they think all cancer is the same. They try to apply information about Hodgkins to non-hodgkins. They think "Breast cancer" is a disease, not a symptom. There over 40 different cancer causes for breast cancer. And the treatments that work are primarily based on the cause not the visible symptom.
This makes studies hard. Most people never learn the cause of their cancer. We are not fortunate enough to always have a single known cause that says "yes you worked in a nuclear waste plant for 6 years" and know that was the cause.
Chemo for example in Hodgkin's Lymphoma increase your 5 year survival chances by 45%. But if you have Smoking related Lung Cancer it is less than 2% difference.
Nature.com rarely produces articles that are informed. They push an agenda of Holistic medicine at the expense of scientific research. I am all for non-traditional medicine, but I don't discount the advances from University and Clinical research.