Littermate control mice lacking an inducible Cre recombinase (genotype Ptf1a+/+; KrasLSL-G12D/+; Trp53LSL-R270H/+; Rosa26LSL-mCL/LSL-mCL; or KP) were injected with tamoxifen and monitored for tumor development for up to one year. Here, PTF1A is linked to neoplasm.