PURPOSE: The radiosensitivity of tissues is essentially influenced by hypoxia. Based on the oxygen effect a new therapeutic modality has been developed to protect healthy tissues while hypoxic breathing during irradiation. PATIENTS AND METHOD: The effect of hypoxic breathing (8.1% O2) on the pO2 in metastatic lymph nodes was studied in 14 patients. Tissue oxygenation was assessed using a polarographic electrode system. RESULTS: The median pO2 was 19.6 mm Hg prior to hypoxic breathing with a great intra- and intertumoral variability. The relative frequency of pO2-values < 5 mm Hg was between 0 and 88%. During hypoxic breathing we registered no significant changes in the mean, the median or the pO2 values < 5 mm Hg. CONCLUSIONS: In metastatic lymph nodes can be found chronic hypoxia with great inter- and intratumoral pO2 variability. The hypoxic breathing (8.1% O2) shows no significant modifications of the tumor oxygenation with increased pO2 variability. This fact explains the experimental and clinical experience, that the hypoxic breathing (8 to 10% O2) protects the healthy tissue without changes in the radiosensitivity of chronic hypoxic tumor tissue.
PURPOSE: The radiosensitivity of tissues is essentially influenced by hypoxia. Based on the oxygen effect a new therapeutic modality has been developed to protect healthy tissues while hypoxic breathing during irradiation. PATIENTS AND METHOD: The effect of hypoxic breathing (8.1% O2) on the pO2 in metastatic lymph nodes was studied in 14 patients. Tissue oxygenation was assessed using a polarographic electrode system. RESULTS: The median pO2 was 19.6 mm Hg prior to hypoxic breathing with a great intra- and intertumoral variability. The relative frequency of pO2-values < 5 mm Hg was between 0 and 88%. During hypoxic breathing we registered no significant changes in the mean, the median or the pO2 values < 5 mm Hg. CONCLUSIONS: In metastatic lymph nodes can be found chronic hypoxia with great inter- and intratumoral pO2 variability. The hypoxic breathing (8.1% O2) shows no significant modifications of the tumor oxygenation with increased pO2 variability. This fact explains the experimental and clinical experience, that the hypoxic breathing (8 to 10% O2) protects the healthy tissue without changes in the radiosensitivity of chronic hypoxic tumor tissue.
Authors: R A Gatenby; H B Kessler; J S Rosenblum; L R Coia; P J Moldofsky; W H Hartz; G J Broder Journal: Int J Radiat Oncol Biol Phys Date: 1988-05 Impact factor: 7.038
Authors: M Höckel; C Knoop; K Schlenger; B Vorndran; E Baussmann; M Mitze; P G Knapstein; P Vaupel Journal: Radiother Oncol Date: 1993-01 Impact factor: 6.280