MSLN and neoplasm: Over two-thirds of TNBC in our series demonstrated at least focal MSLN staining in at least 1% of tumor cells (Table 2), a percentage similar to that reported by Tchou et al [46], but we documented higher rates of MSLN reactivity in non-TNBC (45% showing at least focal staining, and 16% with substantial MSLN expression in our study versus only 3% in a prior study [46]).