Maureen, I had stage 4 cancer of the tongue and lymph nodes on the left side. I started out with surgery then started radiation a few weeks later. I also had three sessions of chemo concurrently with the radiation. Since radiation is the primary treatment for head and neck cancer the chemo was given as extra treatment kind of as insurance. My doctors didn't call it a "boost" but they told me that there was less chance of the cancer returning if I had the chemo. My chemo treaments were one early during the radiation treatments, one in the middle, and one toward the end. Each chemo session was around three hours long.