[Can the metachromatic index be of help in cancer diagnosis?]

Histological preparations of colon, which contain benign cells, maligne cells, and also transient forms, were stained with spectral-pure Thionine-, Methylene Blue- and Capribluesolutions of different concentrations. The stained samples were examined spectroscopically. We observed a bathochromic shift of the absorbance spectra in cancer cells in comparison with benign cells. Hence the metachromatic index is reduced. The results are discussed in relation to the morphologic changes, the dye DNA binding ratios, and in view of their general use in cancer diagnosis.