In non-PC patients (I.e where Bone mets much less common)? Of the almost exactly the same distributions and magnitude. I'd suggest that borders on the incredible.
I think you are missing the fact that it looks like they only tested CTx in patients with cancers where bone mets are reasonably common. Thus in the non-prostate cohort where they tested Ctx, over 60% (46/73) in fact had bone mets. So it's not too surprising that the effect was similar.