 |
PETER D. GRIMM, D.O.* JOHN C. BLASKO, M.D.,* JOHN E. SYLVESTER, M.D.,*t ROBERT M. MEIER, M.D.,* AND WILLIAM CAVANAGH, B.S*
Prostate Cancer Treatment Center, Seattle, WA, Swedish Medical Center, Seattle,WA; Puget Sound Tumor Institute, Edmonds, WA
Purpose: To report 10-year biochemical (prostate-specific antigen[PSA] outcomes for patients treated with 125I brachytherapy as monotherapy for early-stage prostate cancer.
Methods and Materials: One hundred and twenty-five consecutively treated patients with clinical Stage T1- T2b prostate cancer were treated with 125I brachytherapy as monotherapy, and followed with PSA determinations. Kaplan-Meier estimates of PSA progrcssion-free survival (PFS), on the basis of a two consecutive elevations of PSA, were calculated. Aggregate PSA response by time interval was assessed. Comparisons were made to an earlier treated cohort.
Results: The overa PSA PFS rate achieved at 10 years was 87% for low-risk patients (PSA < 10, Gleason Sum 2-6. T1-T2b). Of 59 patients (47%) followed beyond 7 years, 51 (86%) had serum psAs lees than 0.5 ng/mL; 48 (81 %) had serum PSAs less than 0.2. ng/mL. Failures were local, 3.0%; distant, 3.0%. No patients have died of prostate carcinoma. The proportion of patients with PSA < 0.2 ng/mL continued to increase until at least 7-8 years posttherapy. A plot of PSA PFS against the proportion of patients achieving serum PSA or less than 0.2 ng/ml suggestsa convergence of these two endpoints at 10 years. Paticnts "treated In the era of this study (1988-1990) experienced a statistically improved: PFS compared with an earlier era (1986-1987). This difference appears independent of patient selection, suggesting that the maturation of the technique rcsultcd in improved biochemical control.
Conclusion: With modern technique, monotherapy with 125I achieves a high rate (87%) of biochemical and clinical control in patients with low-risk disease at 10 years. The decline of PSA following brachytherapy with low-dose rate isotopes can be protracted. Absolute PSA and PFS curves merge, and are comparablc at 10 years.
copyright 2001 Kisevler Science Inc.
|
