Table 1. The growth of ECA109 xenografts in different groups of mice.

Treatment	Doubling time (days)	Absolute growth delay (days)*	Normalized growth delay (days)†	Enhancement factor
Control	4.07 ± 0.56
rh-Endo	5.01 ± 0.66	0.94 (5.01-4.07)
IR	4.67 ± 1.65	0.60 (4.67-4.07)
IR + rh-Endo	6.79 ± 0.81	2.72 (6.79-4.07)	1.76 (2.72-0.94)	2.93 (1.76/0.60)

IR, irradiation.

^*Tumor doubling time in the treatment groups minus that of the control group.

^†Subtraction of the absolute growth delay of the tumor in the group treated with rh-Endo alone from that of the group treated with both irradiation and rh-Endo.