Gemlin-
Just to be clear, that reference was among a Swedish cohort, and many men were treated with radiation doses that would now be considered substandard (the "irrelevance" of long term retrospective data!). While the RT cohort was treated heterogeneously, you can see the steady improvement over time from RT in Figure 3 (whereas RP outcomes improved little).
To have a true comparison, we need a randomized trial. ProtecT was the first trial where favorable risk patients were randomized to RP, RT, or AS. And the ten-year outcomes were no different. However, even there the radiation doses were too low (74 Gy).
The oncological advantage of radiation, and particularly with augmented radiation, over surgery is mostly among unfavorable risk patients.
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