Squamous epithelial dysplasia associated with squamous cell carcinoma of the esophagus.

To investigate the relationship between dysplasia and carcinoma of the esophagus, 159 cases of esophageal carcinoma without any preoperative treatment were reviewed retrospectively. There were 75 dysplastic lesions in 32 cases (20.1%). The incidence of co-existence of dysplastic lesions was 0, 58.3, 31.3, 20.8 and 11.4% in intra-epithelial, mucosal and submucosal cancers and those invading the proper muscular layer and adventitia, respectively. Thus, excluding the cases of intra-epithelial carcinoma, the less advanced the lesion, the higher the incidence of dysplasia. Epithelial dysplastic lesions were classified as 12 with mild, 33 with moderate and 30 with severe degrees of dysplasia. Although the continuity of dysplastic lesions to the areas of carcinoma was not so frequent (48.0%), it was more often encountered in severe dysplasia rather than in moderate or mild dysplasia, which suggested some relationship between the severity of dysplasia and carcinoma. In the cases with a dysplastic lesion the multiplicity of squamous cell carcinoma and the intra-epithelial spread of the main lesion were more frequently seen (P < 0.001), suggesting a multicentric occurrence of dysplastic lesions and carcinomas.