HGF and posterior cortical atrophy: Our prior studies of another potential surrogate of HGF signaling, soluble Met ectodomain (sMet), showed that sMet levels in plasma and urine correlated directly with burden of PCa tumor xenografts in mice [22], and that urinary sMet was significantly higher in metastatic PCa patients relative to patients with organ-confined disease or controls not known to have any form of cancer [23].