I typically do 50 as well but to be fair pCR and survival in the Tepper CALGB study and CROSS were essentially identical (for both SCC and AC subtypes) despite different doses. The Tepper study closed early so the power isn't great but it does suggest that perhaps the possible pathologic gains with 50 vs 41.4 for patients that don't end up having surgery might not be that big.
I have a few issues with this analysis. First, there is not a lot of detail given to help me understand the characteristics of patients in each group. Second, they are trying to pull a bit of a fast one with the survival conclusion. Look at OS closer. At all but one timepoint its not that low dose is better than high dose. Its actually that low and high dose are similar and better than medium dose. But for PFS it looks like there is more of a negative correlation with dose. How does one see a 40% (relative) decrease in 5 year PFS between 41.4 and 50.4 with no corresponding difference in OS? Without knowing more about the groups I don't really have enough context to understand what is going on. Furthermore, I am very hard pressed to come up with a biologic reason that higher dose radiation would compromise distant disease control. Across the board decrements in survival would be easier to understand but that is not what they are getting. Seems like there is a high probability of some kind (more likely multiple kinds) of bias at play.
