I've asked around a bit. LTFU is a concern here, as in any trial. I'd think that placebo has a greater issue with that than the treatment arm, because it IS a chemo treatment and side effects should be obvious to docs. The doc would know, but fortunately RFA only still works well for at least 5-9 months, so we'll have that much history before censoring for LTFUs.
I mentioned this on IV, but if the initial ablation fails, they still will have burned quite a bit away, so the second try would be on a much smaller tumor, and thus have a greater chance of success.
Regards,
Trond