Table 1.

Tumor control dose 50 (TCD₅₀) for radiation only or radiation combined with hypoxic targeting agent(s) in mice

Treatmenta)	TCD50b) (±95% CI)
Radiation alone (3 x 15 Gy)	29.7 (22.9-38.5)
Radiation + 1 x nimorazole	20.1 (11.7-34.3)
Radiation + 3 x nimorazole	2.5 (0.5-13.7)*
Radiation + 1 x nimorazole and carbogen	22.9 (16.2-32.4)
Radiation + 3 x nimorazole and carbogen	<1.0 (not measurable)
Radiation + 1 x OXi4503	12.2 (6.0-24.9)*
Radiation + 3 x OXi4503	12.1 (7.9-18.6)*
Radiation + 1 x hyperthermia	10.1 (7.0-14.6)*
Radiation + 3 x hyperthermia	8.6 (4.5-16.6)*
Radiation + 1 x OXi4503 and hyperthermia	1.9 (0.4-8.5)*

The study showing that tumor control dose 50 (TCD₅₀) can dramatically be reduced when high dose (15 Gy) irradiation is combined with hypoxic modifications such as nimorazole (Radiation alone), nicotinamide (Radiation + 3 × nimorazole) and carbogen (Radiation + 3 × nimorazole and carbogen), and hyperthermia. CI, confidence interval.

^a)All modifiers were given with either each 15 Gy fraction (3×) or only the last 15 Gy fraction (1×).

^b)TCD₅₀, clamped top-up radiation dose needed to control 50% of the tumors. Data were obtained from Figures 1 and 2 [52].

^*indicates a statistically significant difference when compared to radiation alone (p < 0.05).

Adapted from Wittenborn and Horsman [52] with permission of Taylor & Francis.