Grays is a measure used in radiology. There are two version. I am told the old version uses centigray, more common today is just grays. Usually a number like 75 grays is mentioned. 75 grays is also 7500 centigrays. So 200 centigrays is 2 grays. 30 x 2 = 60 grays total.

The term fraction is used to describe the daily dose you receive.

Since the radiation is mapped across the area and receives different dosages the number is an average, not exact to any given area as it differs.

60 is on the low end of the range for effective killing effect.

Good luck

Don
Male, 57 - Great health except C
Dec '12
DX: BOT SCC T2N2bMx, Stage 4a, HPV+, multiple nodes
1 tooth out
Jan '13
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Tumor Board -induction TPF (3 cycles), seq CRT
4-6/2013
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