Our experience (Demiroz C et al., IJROBP 2011) includes 26 patients with ENB, all of whom had N0 neck at diagnosis, and none had received neck RT (about half received primary site adjuvant RT). The results were: 26% neck recurrences: 6/19 in  Kadish  B and 1/5 in Kadish C. Most recurrences...

All situations. I use an AP field with a midline block and give 50 Gy in 25 fractions at Dmax. It is effective.

I do a thorough workup postop, including a PET/CT and MRI simulation. I don't typically radiate both sides of the neck if it is Kadesh A.

I always treat the neck. Bilateral if across midline. I generally use a separate AP field with a midline block. I have not seen much additional toxicity nor have I seen marginal misses or infield failures.