PTEN and neoplasm: Mutational status of selected genes was assessed on tumor tissue or circulating tumor DNA (ctDNA) with different methods, including Sanger sequencing (Ma et al., 2017), real-time PCR (RT-PCR) (Turner et al., 2019), digital droplet PCR (ddPCR) (Jones et al., 2020; Smyth et al., 2020), and NGS (Kim et al., 2017; Oliveira et al., 2019; Schmid et al., 2020a), whereas PTEN expression was universally determined by tissue IHC.