Table 2.

Effect of very low dose radiation on tumor growth in C3H mice.

Tumor	p53 Status	Time in days for tumor to grow from 300 mm3 to 1000 mm3 in volume			Absolute growth delaya,b,c	P value (t-test)
		Untreated	5 Gy × 5 Days	5 mGy – 15 min – 5 Gy × 5 Days
SA-NH	WT	3.6 ± 70.3	7.2 ± 70.9	5.3 ± 70.4	3.6a	<0.001
					1.7b	=0.001
					−1.9c	=0.032
FSa	Mutant	4.1 ± 70.6	7.4 ± 70.8	11.9 ± 70.7	3.3a	=0.005
					7.8b	<0.001
					4.5c	<0.001

^aTime in days for tumors exposed to 5 Gy for 5 consecutive days to grow from 300 mm³ to 1000 mm³ minus the time in days for untreated tumors to grow from 300 mm³ to 1000 mm³.

^bTime in days for tumors exposed to 5 mGy – 15 min – 5 Gy for 5 consecutive days to grow from 300 mm³ to 1000 mm³ minus the time in days for untreated tumors to grow from 300 mm³ to 1000 mm³.

^cTime in days for tumors exposed to 5 mGy – 15 min – 5 Gy for 5 consecutive days to grow from 300 mm³ to 1000 mm³ minus the time in days for tumors exposed to 5 Gy for 5 consecutive days to grow from 300 mm³ to 1000 mm³