I had the six weekly treatments, and it seemed like they thought it was the standard at that time. Or maybe it was just the standard for 'just in case' when the nodes came back clear but they were paranoid anyway. My situation was a little odd ... I'd had surgery for the initial cancer that May, had the neck thingummy in August which was all-clear, and then the tongue recurrence in December. So I think they weren't taking any chances, though the tongue situation was minimal both times.