Table V.

Numbers of patients from the radiation pneumonitis group who received different radiotherapy exposures.

Ratio	≥60 Gy	35 to ≤59.9 Gy	15 to ≤34.9 Gy	5 to ≤14.9 Gy	P-value
L/B ≥3	4	0	0	0	0.026
2.5 ≤L/B <3	4	3	0	0	0.018
2 ≤L/B <2.5	0	5	3	0	0.625
1 ≤L/B <2	0	0	5	8	2.054

L/B is the mean standardized uptake value (SUV) of radiated lung tissues/the average SUV of non-radiated lung tissues. The value of non-radiated lung tissues is equal to that of local lung tissues with an exposure dose of ≤5 Gy (the lung tissues that are non-circumscribed by the 10% equal dose curve).