[Occurrence of non-metaplastic squamous epithelium within the larynx and its relation to the development of cancer]

The study is concerned with the occurrence and distribution of squamous epithelial areas in the human larynx as well as with the question as to whether inferences with regard to the development of inner laryngeal carcinomas can be made from their location. For this purpose, macroscopic epithelial staining was carried out on 104 cadaver larynxes and the results compared with the tumor location established in macroscopic serial sections of approximately 100 surgical preparations of extirpated larynxes. Special interest was devoted above all to the occurrence of squamous epithelium outside the vocal cord level. The authors found special sites of predilection for carcinogenesis which showed an astonishingly striking correlation with the distribution of the squamous epithelium found in the interior of the larynx in all age groups. Direct carcinogenesis from healthy squamous epithelium is discussed as well as the development of cancer from a metaplastic transformation of ciliated epithelium into squamous epithelium. The results constitute a contribution to early diagnosis of inner tumors of the larynx, since on the basis of the results it appears to be indicated that increased specific attention needs to be paid to the parts of the mucosa which display areas of squamous epithelium with a certain regularity in microlaryngoscopy.