| Abstract: |
Purpose: To review the biochemical relapse-free survival (bRFS) rates after treatment with permanent seed implantation (PI), external beam radiotherapy (EBRT) <72 Gy (EBRT <72), EBRT ≥72 Gy (EBRT ≥72), combined seeds and EBRT (COMB), or radical prostatectomy (RP) for clinical Stage T1-T2 localized prostate cancer treated between 1990 and 1998. Methods and Materials: The study population comprised 2991 consecutive patients treated at the Cleveland Clinic Foundation or Memorial Sloan Kettering at Mercy Medical Center. All cases had pretreatment prostate-specific antigen (iPSA) levels and biopsy Gleason scores (bGSs). Neoadjuvant androgen deprivation for ≤6 months was given in 622 cases (21%). No adjuvant therapy was given after local therapy. RP was used for 1034 patients (35%), EBRT <72 for 484 (16%), EBRT ≥72 for 301 (10%), PI for 950 (32%), and COMB for 222 patients (7%). The RP, EBRT <72, EBRT ≥72, and 154 PI patients were treated at Cleveland Clinic Foundation. The median radiation doses in EBRT <72 and EBRT ≥72 case was 68.4 and 78.0 Gy, respectively. The median follow-up time for all cases was 56 months (range 12-145). The median follow-up time for RP, EBRT <72, EBRT ≥72, PI, and COMB was 66, 75, 49, 47, and 46 months, respectively. Biochemical relapse was defined as PSA levels >0.2 for RP cases and three consecutive rising PSA levels (American Society for Therapeutic Radiology Oncology consensus definition) for all other cases. A multivariate analysis for factors affecting the bRFS rates was performed using the following variables: clinical T stage, iPSA, bGS, androgen deprivation, year of treatment, and treatment modality. The multivariate analysis was repeated excluding the EBRT <72 cases. Results: The 5-year bRFS rate for RP, EBRT <72, EBRT ≥72, PI, and COMB was 81%, 51%, 81%, 83%, and 77%, respectively (p <0.001). The 7-year bRFS rate for RP, EBRT <72, EBRT ≥72, PI, and COMB was 76%, 48%, 81%, 75%, and 77%, respectively. Multivariate analysis, including all cases, showed iPSA (p <0.001), bGS (p <0.001), year of therapy (p <0.001), and treatment modality (p <0.001) to be independent predictors of relapse. Because EBRT <72 cases had distinctly worse outcomes, the analysis was repeated after excluding these cases to discern any differences among the other modalities. The multivariate analysis excluding the EBRT <72 cases revealed iPSA (p <0.001), bGS (p <0.001), and year of therapy (p = 0.001) to be the only independent predictors of relapse. Treatment modality (p = 0.95), clinical T stage (p = 0.09), and androgen deprivation (p = 0.56) were not independent predictors for failure. Conclusion: The biochemical failure rates were similar among PI, high-dose (≥72 Gy) EBRT, COMB, and RP for localized prostate cancer. The outcomes were significantly worse for low-dose (<72 Gy) EBRT. © 2004 Elsevier Inc. |
