From what I understand, Cobalt 60 is a type of Gammaknife, which is really stereostatic radiosurgery, and is not really surgery, but a precise form of radiation with minimal effect on surrounding tissue, which was largely used on brain tumors. Gammaknife, Cyberknife are trademarked names.

Linear accelerators, most commonly used, are state of the art radiation machines, such as IMRT, IGRT, VMAT, IORT, Stereostatic Radiosurgery, that deliver customized high doses of x-rays to tumors in all areas, while sparing normal tissue.

http://oralcancerfoundation.org/facts/imrt-radiation/

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