OR51E2 and posterior cortical atrophy: Similarly, Rigau et al. [54] have demonstrated that a combination of urinary prostate-specific G-protein coupled receptor (PSGR), a biomarker over-expressed in PCa tissue, and PCA3 test greatly improved the specificity of PCa detection from 15% (PSGR) and 17% (PCA3) to 34% (PSGRvPCA3) at a high sensitivity (95%).