I should have mentioned the first time. The first time I had radiation it was because the tumor in my tongue was considered too large and deep for surgery. I had no positive nodes per a PET scan but my neck was radiated in addition to my mouth as a precaution.

The second time around, I had a RND on the right side, removing one positive node and 39 clear ones. Although only one node was positive, the cancer had broken out of the node and was invading other tissues and my carotid artery. In the RND they removed a section of my jugular vein, and my SCM muscle on the right. Radiation followed to both side of the neck. As I understood it, it was 'cleanup' as the margins from my positive node removed were not clear from the RND.

I'm not sure how common it is for radiation to be done to the neck in addition to the RND's. I just know in my case it was because they knew there was leftover cancer in there. The doc said he scraped as much suspicious tissue off my carotid as he could without jeopardizing its integrity. It was supposed to be a 1.5 hr procedure and ended up being 4 hrs.