Timeline describing key developments in the generation of patient-derived models. Declines in sequencing costs (orange points); and the emergence of model types, including cell lines, xenografts, organoids, and “next-generation” cell lines, are highlighted (source data: Rygaard and Povlsen, 1969; Jeffreys et al., 1985; The Cancer Genome Atlas, 2005; Wetterstrand, 2016; and references cited in the main text).