Table 6. Specificity comparison of PSA and GSTP1 methylation for PCa diagnosis.

PSA	GSTP1 methylation		Total
	+	－
+	4	24	28
－	6	27	33
Total	10	51	61

P=0.001. GSTP1, glutathione S-transferase Pi-1; PSA, prostate-specific antigen; PCa, prostate cancer.