Optimum fractionation regimen for bleomycin treatment

Abstract

A theoretical analysis was made on the optimum Bleomycin treatment regimen on the basis of the "binding-saturation model" which was proposed for the Bleomycin dose-cell survival relation. The surviving fraction of tumor cells decreased as a function of the number of fractionated treatments up to the optimum fractionation number if the tumor was treated with the same total dose. The effect of cellular sensitivity to the antibiotic, tumor doubling time, treatment interval, and total doses on the optimum regimen was analyzed. The importance of treatment interval and tumor doubling time was emphasized and the short treatment interval was recommended for the clinical use of this antibiotic. The optimum number of fractions increased linearly with the increase of the total dose while the optimum single dose was independent of the total dose. A concept of the tumor control probability of tumors treated with the optimum fractionation regimen was introduced and implications of these analyses in the clinical cancer chemotherapy were discussed.