Your correct, radiation, besides surgery, is the real cure for this cancer, but chemo acts as a radiosensitizer to make radiation work better. Depending on type of chemo that petcentage can range. Sounds like Cisplatin with 3 doses, which is the gold standard, plus chemo works systemically, and may get at any microscopic cancer, if any, outside the radiated field. Many do not go on to complete the 3rd infusion, even 2nd, due to side effects or may even do radiation alone, but the chemo may still be in the body to act as a radiosensitizer for a while.

Good luck.

10/09 T1N2bM0 Tonsil
11/09 Taxo Cisp 5-FU, 6 Months Hosp
01/11 35 IMRT 70Gy 7 Wks
06/11 30 HBO
08/11 RND PNI
06/12 SND PNI LVI
08/12 RND Pec Flap IORT 12 Gy
10/12 25 IMRT 50Gy 6 Wks Taxo Erbitux
10/13 SND
10/13 TBO/Angiograph
10/13 RND Carotid Remove IORT 10Gy PNI
12/13 25 Protons 50Gy 6 Wks Carbo
11/14 All Teeth Extract 30 HBO
03/15 Sequestromy Buccal Flap ORN
09/16 Mandibulectomy Fib Flap Sternotomy
04/17 Regraft hypergranulation Donor Site
06/17 Heart Attack Stent
02/19 Finally Cancer Free Took 10 yrs