GFAP and astrocytoma (excluding glioblastoma): Both studies, and many studies that followed hereafter, show that GFAP expression in astrocytoma is increased compared to healthy brain tissue (Table 1) both at the protein (Delpech et al., 1978; Dittmann et al., 1977; Mauro et al., 1991; Narayan et al., 1986; Palfreyman et al., 1979) and mRNA (Bien‐Moller et al., 2018; Laczko et al., 2007) level.