Relationship between transcerebral passage of tumor cells and brain metastasis.

Quantitative study was carried out on transcerebral passage of tumor cells using Yoshida sarcoma and 6 strains of rat ascites hepatoma. The counting was done every second for 40 sec. In relation to the results obtained, histological study was made on the cerebral metastasis of these tumor cells. Metastatic foci in the brain parenchyma, except the meninges and choroid plexus, were formed by island-forming strains (AH-130, AH-272, and AH-7971) which showed comparatively low passage rate and not be single-cell strains (Yoshida sarcoma, AH-7974F, AH-66F, and AH-13) which showed comparatively high rates. Accordingly, it is obvious that there is a correlation between transcerebral passage rates and brain metastasis formation. The mechanisms of metastasis formation were discussed with special reference to arrest of tumor cells in blood vessels.