[Microscopic derivative spectrum measurement of DNA in nuclei of cancer and precancer cells in carcinoma of gastric cardia].

For comparative study, microscopic derivative spectrophotometry was used to determine the distribution of DNA concentration in nuclei of normal epithelial cells, precancer and exfoliative cancer cells in gastric cardia. By this technic, the relative DNA contents (arbitrary units) can be measured and the first microscopic derivative spectrum of several selected areas in the cellular nucleus can be recorded. The specimens of measurement were: 50 normal epithelial cells, 125 precancer (42 markedly dysplastic cells and 83 suspicious cancer cells) and 111 cancer cells of gastric cardia from 25 patients. The present study showed that, in general, the peak values and differences between the peak values of cancer cells as assayed by the first microscopic derivative spectrum were significantly greater than those of the precancer cells. But 9.6% of those values of the precancer cells were still similar to those of cancer cells. When these conditions were compared by using the biopsy material from the same patient, it was found that these cells were derived from patients with carcinoma of gastric cardia. Thus it is believed that biochemical changes of cells as measured by microscopic derivative spectrophotometry are more sensitive and objective than those by morphology. It would seem that microscopic derivative spectrophotometry would be, at least, a supplementary means of differentiating the cancer cells from the precancer ones.