10-year biochemical (prostate-specific antigen) control of prostate cancer with (125)I brachytherapy.
OBJECTIVE
To report 10-year biochemical (prostate-specific antigen [PSA]) outcomes for patients treated with 125I brachytherapy as monotherapy for early-stage prostate cancer.


METHODS
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 progression-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 overall 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 less 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 a PSA < or =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 of less than 0.2 ng/mL suggests a convergence of these two endpoints at 10 years. Patients 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 resulted in improved biochemical control.


CONCLUSIONS
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 comparable at 10 years.
Grimm
P D
PD
Seattle Prostate Institute, Swedish Medical Center, Seattle, WA 98104, USA. peter@grimm.com
Blasko
J C
JC
Sylvester
J E
JE
Meier
R M
RM
Cavanagh
W
W
D000368:Aged; D001918:Brachytherapy / Q000379:methods*; D016001:Confidence Intervals; D003430:Cross-Sectional Studies; D006801:Humans; D007457:Iodine Radioisotopes / Q000627:therapeutic use*; D008297:Male; D009367:Neoplasm Staging; D011446:Prospective Studies; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000473:pathology / Q000532:radiotherapy*; D013997:Time Factors; D017211:Treatment Failure
D007457:Iodine Radioisotopes; D017430:Prostate-Specific Antigen