QUANTITATIVE STUDY ON THE TRANSPULMONARY PASSAGE OF TUMOR CELLS

抄録

Quantitative analysis was made on uninterrupted transpulmonary passage of cells, employing seven strains of transplantable tumor cells.
When a large number of tumor cells are injected intravenously, some mice die instantaneously and the others survive. The cause of instantaneous death was attributed to the pulmonary embolism by tumor cells, while the uninterrupted passage of cells through the lungs was noted, by means of histological and physical, especially electrocardiographic, examinations.
Number of tumor cells neccessary to cause instantaneous death by pulmonary embolism (LD₅₀) was characteristically different by the injection time and each tumor strain employed.
The largest number of tumor cells which could pass through the lungs during one minute was calculated from the values of LD₅₀ in each velocity of injection. It was noted that the number of passing cells was quite different with each strain of cells. For example, the largest was 86.7×10⁶ of SN36 tumor cells, while the smallest was 2.2×10⁶ of AH-66F. Such difference was discussed in correlation with the size of diameter in each strain of cells.
Based on the results from the experiments and reviewing the past literature, the mechanism of hematogenous metastasis was discussed, emphasizing the significance of circulating tumor cells in the blood stream.