High PSA Not Always a Negative Outcome Predictor
Prostate cancer (PCa) patients with PSA levels above 20 ng/mL are not necessarily at high risk for negative outcomes such as prostate cancer-specific mortality (PCSM), but a higher number of risk factors at diagnosis correlates significantly with unfavorable pathology, a study showed.
The investigation also revealed that biopsy Gleason score is strongest predictor of progression and PCSM.
Martin Spahn, MD, of University Hospital Würzburg in Germany, and colleagues studied 712 men with PSA levels above 20 and who underwent radical prostatectomy (RP) and bilateral pelvic lymphadenectomy.
They classified patients into four risk groups. Group 1 included men who only had a PSA level above 20; group 2 patients had a PSA level above 20 and clinical tumor stage greater than cT2. Group 3 included men who a PSA level above 20 and a biopsy Gleason score above 7. Group 4 consisted of subjects with a PSA level above 20, clinical tumor stage greater than cT2, and a biopsy Gleason score above 7. The mean follow-up period was 78.7 months.
Overall, the proportion of favorable parameters decreased significantly with an increasing number of high-risk factors (27%, 11%, 1.95, and 0% for groups 1, 2, 3, and 4 respectively, the researchers reported in European Urology (2010;58:1-7).
Among subjects in group 1, 33% had pT2 cancer, 57.9% had a pathologic Gleason score below 7, 54% had negative surgical margins, and 85% were lymph node negative. In contrast, among patients in group 4, 2.3% had a pathologic Gleason score below 7 20.5% had negative margins and 49% were lymph node negative.
The 10-year PCSM was 5% for patients with a biopsy Gleason score of 7 or less compared with 35% for those with a biopsy Gleason score of 8 or higher.
Patients who had only a PSA level above 20 and those who also had a clinically locally advanced stage, had estimated 10-year biochemical progression-free rates of 95% and 91%, respectively.
The entire study cohort had a cancer-specific survival rate of 89.8% at 10 years. Patients who had a combination of a PSA level over 20 and high-grade disease, regardless of clinical stage, had a cancer-specific survival rate of 65% at 10 years.
The authors concluded that PCa patients who have a PSA level above 20 are a heterogeneous group. Those with a PSA level above 20 and a biopsy Gleason score of 7 or less are at minimal risk for PCSM “so they are good candidates for surgery,” they noted.
However, patients with a PSA level above 20 and high-grade tumors or those with or without clinically locally advanced disease are at significant risk for PCSM despite undergoing RP and adjuvant or salvage treatments “and should be considered for clinical studies testing new adjuvant treatment modalities.”