The results of radiotherapy combined with hyperbaric oxygen in 9 patients with malignant glioma were compared with those of radiotherapy without hyperbaric O2 in 12 patients. This is the first report of a pilot study of irradiation immediately after exposure to hyperbaric O2 in humans. All patients receiving this treatment showed more than 50% regression of the tumor, and in 4 of them, the tumors disappeared completely. Only 4 out of 12 patients without hyperbaric O2 showed decreases in tumor size, and all 12 patients died within 36 months. So far, this new regimen seems to be a useful form of radiotherapy for malignant gliomas.

Kohshi, Kinoshita, Terashima, Konda, Yokota, Soejima, , , (1996). Radiotherapy after hyperbaric oxygenation for malignant gliomas: a pilot study. Journal of cancer research and clinical oncology, 1996 ;122(11):676-8. https://www.ncbi.nlm.nih.gov/pubmed/8898978