Nevertheless, these data question the level of confidence in ALA-RDT promoted by other authors and the transfer to everyday clinical practice, even in tumors with a relatively high body of evidence (such as glioma and melanoma), as the individual effectiveness might be impaired based on varying oxygen levels, genomic alterations, tumor heterogeneity, and individual expression of amino acid transporter proteins and heme biosynthesis enzymes, as illustrated by Ebrahimi et al. The gene discussed is SLC38A7; the disease is central nervous system cancer.