Table 1. The effects of the life expectancy distribution on cancer initiation.

The table displays the probability of cancer initiation prior to death of the patient for a varying mode of the lifetime distribution, ϕ_mode. Three mutational fitness distributions are considered: α < β, α = β, and α > β. As the life expectancy increases, the probability of cancer initiation before death also increases. Furthermore, the ratio of α to β significantly impacts the initiation probability; when β > α, disadvantageous mutations are more frequent than advantageous mutations, and the probability of a cell accumulating fitness 1 + 1/N (i.e. cancer initiation) is low. When β < α, advantageous mutations are more frequent and thus the probability of initiation is enhanced. The mode of the data fitting current US life expectancy data is ϕ_mode = 80. Parameters used are u = 0.001 and N = 10.