[Study on DNA content and nucleus/cytoplasm ratio of esophageal epithelium during malignant change]

DNA content and nucleus/cytoplasm ratio were assayed in the paracancerous mucosa from 37 cases of esophageal carcinoma by microspectrophotometry (Leitz MPV3). The histopathological diagnosis was made at the same area. In normal epithelium and simple hyperplasia, the relative DNA content was within the range of 2C-4C; cells with DNA content of 4C or greater than 4C were found mostly in invasive carcinoma. There were two different types of DNA content histogram observed in atypical hyperplasia and carcinoma in situ. One type was similar to simple hyperplasia and the other type was similar to invasive carcinoma. These results indicated that two different malignant features might be obtained under the same histopathological diagnosis. The nucleus/cytoplasm ratio in simple hyperplasia was close to that of normal mucosa. In atypical hyperplasia and carcinoma in situ, especially in the middle and superficial layers of the epithelium, the nucleus/cytoplasm ratio increased markedly, which indicated that the cells in these layers were poorly differentiated.