FOLH1 and neoplasm: However, given the minimal expression of the PSMA biomarker, using the DDSI metric for the PC-3 tumors did not improve the tumor to prostate (ROC AUC = 0.34), adipose (ROC AUC = 0.18) or muscle (ROC AUC = 0.21), which was not diagnostically useful [Figs. 4(d)–4(e)].