G6PD and neoplasm: The Kaplan-Meier plot has not been adjusted for clinical prognostic factors or risk factors; therefore, it remains to be determined whether this reduction in disease-free survival is dependent on G6PD or whether G6PD is acting as a surrogate marker of Gleason score, prostate-specific antigen (PSA), or tumor category indicative of more advanced and aggressive disease (Fig. 2F).