[Morphological changes in laryngeal cancer after preoperative radiation treatment under different oxygen regimens].

A comparative histological investigation of laryngeal cancer following preoperative irradiation in high pressure oxygenation chamber and under standard conditions established a relatively higher effectiveness of the former procedure. In the zone of exposure, foci of "continued" growth attributed by the authors to the clonal composition to tumor as well as foci of "newly-developed" carcinoma in situ accounted for by multicentricity of cancer in the larynx were observed against the background of highly-pronounced radiation injuries. Discrepancies in evaluating the effectiveness of radiation treatment in clinic and by histological procedures were established: an unjustified clinical diagnosis of malignancy in cases of "dead" tumor proved to be as high as 38%.