title: Exposure time and frequency of irradiation in brain tumours.
abstract: The survival of a group of patients with malignant gliomas of the brain submitted to radical surgery and radiotherapy was studied. The average survival was nearly 4 times longer with X-ray treatment than with cobalt 60 irradiation when a comparison was made between 24 patients with glioblasto-astroblastoma (grade 3-4) who received one or the other type of treatment (12 patients in each group). These results are ascribed to the fact that the daily exposures to X-ray were much longer than with cobalt and so, during those prolonged sessions, a greater number of tumour cells could be destroyed as they successively reached the pre-mitotic period of enhanced vulnerability to radiation. A smaller group of patients irradiated with linear accelerators fared worse than those who received X-ray treatment. Changes to the parameters of irradiation used at the present time with cobalt units or linear accelerators are suggested.
mesh_terms: D001254:Astrocytoma / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D001932:Brain Neoplasms / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D003037:Cobalt Radioisotopes / Q000627:therapeutic use; D003131:Combined Modality Therapy; D005500:Follow-Up Studies; D005910:Glioma / Q000000981:diagnostic imaging / Q000401:mortality / Q000601:surgery / Q000628:therapy*; D006801:Humans; D011859:Radiography; D011879:Radiotherapy Dosage
chemical_list: D003037:Cobalt Radioisotopes