CARBOGEN BREATHING DURING RADIATION-THERAPY - RADIATION-THERAPY ONCOLOGY GROUP-STUDY

The Radiation Therapy Oncology Group (RTOG) Study, in which 254 patients were analyzed, adjunctive carbogen breathing in irradiation of carcinomas of the oral cavity, oropharynx, nasopharynx, hypopharynx, and larynx failed to bring about a gain in survival at any of these sites. In only two of the five regional subgroups did results show any improvement with respect to patients in the Carbogen group as compared to those in the Air group, i.e., the larynx and hypopharynx subgroups. Since both of these subgroups contained relatively small numbers of patients (42 larynx, 39 hypopharynx), it was not possible to declare these improvements as definitely due to carbogen breathing. In the case of the larynx subgroup, improvement might have been due to the slightly unequal distribution with respect to T-stage; in either subgroup, the possibility that apparent improvement was due to nothing more than random variation could not be ruled out. In the subgroups with larger numbers of patients, i.e., the oral cavity and oropharynx groups, there was no demonstrated improvement accompanying carbogen breathing. © 1979.