Changes in oxygenation patterns of locally advanced recurrent tumors under thermoradiotherapy.

Oxygen tension distributions (pO2) were measured in 10 patients with recurrent soft tissue sarcoma (n = 4), recurrent rectal cancer (n = 2), recurrent breast cancer (n = 3) and recurrent neck nodes (n = 1) using computerized pO2 histography. Measurements were performed pretherapeutically and 24 hours after the first cytotoxic hyperthermic treatment. In one patient an increase of the mean pO2 value was evident after hyperthermia. The other 9 patients showed a significant decrease in the mean pO2 values after hyperthermia. Pooled pO2 distributions of measurements before and after hyperthermia differ statistically significant (p < 0.01). The median pO2 from 1248 measurements before hyperthermia is 18.9 mmHg, whereas the median pO2 from 1263 measurements after hyperthermia is 9.4 mmHg.