Recently, we identified the novel protein D-GPCR (Dresden G protein-coupled receptor) which is selectively overexpressed in human prostate cancer (PCa) and belongs to the subfamily of odorant-like orphan GPCRs. Quantification of D-GPCR transcripts in paired malignant and non-malignant prostate tissues of 106 patients with primary PCa by real-time PCR demonstrated a significant up-regulation of this gene in tumor samples. Furthermore, its expression increases with higher tumor stages and grades. The evaluation of D-GPCR expression as a potential molecular tumor marker was performed by receiver-operating characteristic curve (ROC) analysis resulting in an area under the curve (AUC) value of 0.6452. Hence, the evaluation of D-GPCR as possible additive diagnostic tool and putative therapy target appears promising.