To estimate the establishment of resistance, we define WT\documentclass[12pt]{minimal}\usepackage{amsmath}\usepackage{wasysym}\usepackage{amsfonts}\usepackage{amssymb}\usepackage{amsbsy}\usepackage{mathrsfs}\usepackage{upgreek}\setlength{\oddsidemargin}{-69pt}\begin{document}$$_{1/2}$$\end{document}1/2 as the time that would take a tumour to include a cell population where 50% of the cells carry resistance mutations (here “wild type” refers to the initial state of the molecular drug target, which in FLT3 includes an ITD activating mutation). This evidence concerns the gene FLT3 and neoplasm.