Monotherapy for Stage T1/T2 Prostate Cancer: Radical Prostatectomy, External Beam Radiotherapy, or Permanent Prostate Brachytherapy

Reviewer: Heather Jones, MD
OncoLink
Last Modified: October 7, 2002

Presenter: L. Potters
Presenter's Affiliation: Department of Radiation Oncology, Memorial Sloan Kettering at Mercy Medical Center, Rockville Centre, NY, USA
Type of Session: Scientific

Background

Tumors confined to the prostate, stages T1-2N0 are generally managed by radical surgery or radiation therapy. Controversies exist as to the optimal mode of treatment and comparisons between the two are limited. This study reviewed the biochemical relapse-free survival after permanent seed implantation, external beam radiotherapy (EBRT) to a minimum 70 Gy, or radical prostatectomy (RP) for clinically localized stage T1/T2 adenocarcinoma of the prostate.

Materials and Methods

The study population comprised of 1866 consecutively treated clinical stage T1-T2
All pts received only their designated monotherapy without neo-adjuvant or adjuvant hormonal therapy.
All cases had a recorded pretreatment PSA level and biopsy Gleason score.
The median follow-up time was 54 months for all cases (50 months for permanent seed implantation cases, 55 months for EBRT cases, and 62 months for RP.
The distribution of T1-T2a versus T2b stages was as follows: EBRT 93% vs 7%; permanent seed implantation 94% vs 6%; RP 96% vs 4% (p=0.031).
The distribution of pretreatment PSA <= 10 ng/ml versus >10 ng/ml was as follows: EBRT 72% vs 28%; permanent seed implantation 74% vs 26%; RP 75% vs 25% (p=0.66).
The distribution of biopsy Gleason score <= 6 versus >6 was as follows: EBRT 71% vs 29%; permanent seed implantation 78% vs 22%; RP 77% vs 23% (p=0.044).
Biochemical relapse was defined as any detectable PSA value > 0.2 ng/ml for RP pts, and 3 consecutive PSA value rises for the EBRT and permanent seed implantation cases. Any adjuvant therapy was censored as a failure regardless of initial therapy.

Results

The 7-year biochemical relapse-free survival rates for permanent seed implantation vs EBRT vs RP were 74%, 77% and 79%, respectively.
Multivariate analysis identified pretreatment PSA (p<0.001), biopsy Gleason score (p<0.001), and clinical T stage (p=0.035) as independent predictors for biochemical relapse-free survival.
Treatment modality (p=0.57), age (p=0.58), and race (p=0.19) were not independent predictors of biochemical relapse-free survival.

Author's Conclusions

Biochemical failure rates are similar between permanent seed implantation, EBRT, and RP as monotherapy in this patient cohort of consecutively treated patients. Pretreatment PSA and biopsy Gleason Score are important predictors of outcome in early stage prostate cancer.

Clinical/Scientific Implications

Patients with early stage prostate cancer often find themselves attempting to wade through a great deal of information before deciding on an appropriate therapy for the treatment of their cancer. Physicians often find themselves counseling their patients about various treatment options. Since there are no direct comparisons between surgery, EBRT and prostate implant, in the form of randomize studies, we are forced to depend on retrospective reviews. A large well-done retrospective review such as this helps to guide recommendations to patients and gives physicians insight into important prognostic factors. A more defined nomogram of predictive factors may lead to more refined patient selection for monotherapy in the future.

Oncolink's ASTRO Coverage made possible by an unrestricted Educational Grant from Ortho Biotech.