Kyle, I'm another who went through 6 weeks of rad without a PEG. It got tough towards the end, but I managed to get through with less than 10 lbs lost weight. I lost the ability (and the will) to eat anything solid in week 2, and it was 6 weeks post treatment before I could really eat anything solid afterwards.

Tough, yes. It can be done though. For me, It was a reluctance to go back to a tube after having one during surgery. I hated it enough then to be determined to get though Rad without one
Wayne