The chief result being reported here is in the mouse model, it's not 100-some people filling out a questionnaire that got them on the cover of the journal.
While I respect the need for these longterm survey data collection efforts, I am not sure I would frankly trust that survey to even accurately be able to tease out high-intensity vs low-intensity efforts from people participating in the study.
And the tie-in from the cohort survey results back into the motivation for the mouse study just isn't done at all. I mean out of their 148 patients with SEER scores, they make no mention at all at metastatic disease occurence or even attempt to tie that figure back to exercise intensity . . .
> The human data, obtained from an epidemiological study that monitored 3,000 individuals for about 20 years, indicated 72% less metastatic cancer in participants who reported regular aerobic activity at high intensity, compared to those who did not engage in physical exercise.
"As our focus was on the relationship between exercise and cancer, we used a propensity score of multinomial logistic regression to control for key variables in the diet assessed using a validated questionnaire."
So the 73% figure is drawn from a small number of cases that were significantly weighted. I'd be interested to hear what people who know this field think about this result separate from the mouse/human exercise stuff.