Micro-Incineration of Epithelial Tumours with Regard to Radiosensitivity

Abstract

The problem of the sensitivity of tumours to irradiation has commanded an increased amount of attention during recent years, and each of several rival theories has its following both in Europe and America. It is not necessary for the purpose of this paper to discuss all these theories, but only to consider that one which relates radiosensitivity to the nucleus of the cell. Marshak and Bollman (1) have suggested that the amount of radiation absorbed is directly dependent upon the amount of chromatin in the nucleus. Dustin (2) and others have shown that the nucleus is most vulnerable to irradiation during the early stages of mitosis, that is to say during the most hyperchromatic phases. It is well recognized that the cells of a malignant epithelial tumour are more sensitive to irradiation than their normal prototypes, and in this connection the observation of Dudgeon and Barrett (3) that the malignant nucleus is more haematoxyphil than the benign is of importance, since it is to be suggested here that the radiosensitivity of a cell varies with the amount of nuclear chromatin material. Scott (4), by the technic of micro-incineration, demonstrated that the inorganic content of cell nuclei corresponded with the chromatin material, and Scott and Horning (5), incinerating breast carcinomata, found that the inorganic content of nuclei of malignant cells appeared higher than that of normal breast cells.