The effect of non-uniformity fractionation for tumor metastatic abilities

Purpose/background: In recent years, the local control of tumor after radiotherapy has shown a remarkable improvement due to the widespread of the particle beam therapy, IMRT etc.. However, the survival rate of the patients is not satisfied because of the recurrence or distant metastasis. There is an urgent need to search for therapies to control the metastasis. Hyperfractionation is the mainstream of the recent radiotherapy, and the fraction size is getting smaller. Our previous study, however, showed the migration and invasion abilities of tumor cells were enhanced by low-LET radiations at the low-dose region. Small fraction size in hyperfractionation might promote the metastasis. The aim of this study is to examine the effect of non-uniformity fractionation for cell survival and metastatic potential.