Preoperative serum levels of early prostate cancer antigen (EPCA) predict prostate cancer progression in patients undergoing radical prostatectomy.

BACKGROUND

Early prostate cancer antigen (EPCA) has been shown a prostate cancer (PCa)-associated nuclear matrix protein, however, its serum status and prognostic power in patients with PCa are unknown. The goals of this study are to measure preoperative serum EPCA levels in a cohort of PCa patients who were treated with radical prostatectomy (RP), and to investigate whether serum EPCA levels would independently predict cancer prognosis after the surgery.

METHODS

The study group consisted of 109 consecutive patients with clinically localized PCa who were candidates for RP. Serum EPCA levels were measured by ELISA prior to the surgery, and were correlated with pathologic parameters and clinical outcomes postoperatively.

RESULTS

A total of 106 patients underwent RP. Preoperative mean serum EPCA level in RP patients (15.84 ± 3.63 ng/ml) was significantly higher than that in healthy subjects (4.62 ± 1.15 ng/ml) (P < 0.001), but serum EPCA levels in the both groups were statistically lower than the levels in patients with PCa metastatic to regional lymph nodes (27.83 ± 6.22 ng/ml) and metastatic to bone (28.50 ± 6.67 ng/ml) (all P's < 0.001). In patients who progressed during follow-up, preoperative serum mean EPCA levels were higher in those with aggressive disease progression (27.64 ± 5.48 ng/ml) compared with nonaggressive disease progression (18.15 ± 4.63 ng/ml; P < 0.001). In pre- and postoperative multivariate analyses, preoperative serum EPCA level was an independent predictor for disease progression (Hazards Ratio = 5.016, P < 0.001 and Hazards Ratio = 4.305, P < 0.001, respectively).

CONCLUSIONS

Preoperative serum EPCA level is significantly elevated in localized PCa patients with metastatic disease and strongly predicts cancer progression postoperatively.