Tumour oxygenation is increased by hyperthermia at mild temperatures

Figures & data

Figure 1. Frequency distribution of pO₂ in R3230 AC tumours following heating at 42.5 and 43.5°C for 30 or 60 min. N = number of tumours studied; n = number of pO₂ values measured. The mean and median pO₂ values in each tumour were obtained and their average for each experimental group ±1 SE is shown.

Figure 2. The % frequency of pO₂ readings below 5 mm Hg in R3230 AC tumours heated at different temperatures for 30 min are shown. An average for each group ±1 SE is shown.

Table I.  pO₂ values in R3230 AC tumours heated for 30 or 60 min at 40.5–43.5°C.

Treatment	N^†	n^‡	Mean pO2*	Median pO2*	%pO2 < 5.0 mm Hg^§
Control	25	3431	9.8 ± 0.6	3.7 ± 0.3	62.0 ± 2.1
40.5°C, 30 m	20	2099	14.4 ± 0.9^§	5.4 ± 0.7^§	55.4 ± 2.7^§
40.5°C, 60 m	21	2009	14.6 ± 1.1^§	4.2 ± 0.4	56.9 ± 1.9
41.5°C, 30 m	25	2228	14.9 ± 0.8^§	5.9 ± 0.6^§	52.7 ± 2.0^§
41.5°C, 60 m	26	3156	13.4 ± 0.8^§	6.5 ± 0.8^§	50.3 ± 2.8^§
42.5°C, 30 m	21	1938	20.2 ± 1.4^§	12.2 ± 1.8^§	37.1 ± 2.9^§
42.5°C, 60 m	18	2514	10.4 ± 0.8	3.7 ± 0.5	60.5 ± 3.0
43.5°C, 30 m	17	1889	20.5 ± 2.1^§	12.6 ± 1.8^§	29.3 ± 3.5^§
43.5°C, 60 m	13	1418	6.3 ± 0.5	2.1 ± 0.2	78.8 ± 1.7

^†Number of tumours; ^‡number of pO₂ readings; *average ± 1 SE; ^§significantly larger than control values by p < 005.