Equivalent biochemical
failure-free survival after external beam radiation therapy or radical prostatectomy in
patients with a pretreatment prostate specific antigen of > 4-20 ng/ml.
D'Amico AV, Whittington R, Kaplan I, Beard C, Jiroutek M, Malkowicz SB, Wein A, Coleman
CN. Int J Radiat Oncol Biol Phys 1997 Mar 15;37(5):1053-8
Joint Center for Radiation Therapy, Harvard Medical School, Boston, MA 02215, USA.
PURPOSE: Biochemical failure-free survival stratified by the pretreatment
prostate-specific antigen (PSA) and biopsy Gleason score (bGl) is determined for prostate
cancer patients managed definitively with external beam radiation therapy or radical
retropubic prostatectomy. METHODS AND MATERIALS: A Cox regression multivariable analysis
evaluating the variables of PSA, bGl, and clinical stage was used to evaluate the end
point of time to PSA failure in 867 and 757 consecutive prostate cancer patients
managed definitively with external beam radiation therapy or radical retropubic
prostatectomy, respectively. PSA failure-free survival was determined using
Kaplan-Meier analysis. Comparisons were made using the log rank test. RESULTS: The
pretreatment PSA, bGl, and clinical stage (T3,4 vs. T1,T2) were found to be independent
predictors of time to post-treatment PSA failure for both surgically and radiation managed
patients using Cox regression multivariable analysis. Patients with a pretreatment PSA of
> 4 ng/ml and < or = 20 ng/ml could be classified into risk groups for time to
post-therapy PSA failure: low = PSA > 4-10 ng/ml and bGl < or = 4; intermediate =
PSA > 4-10 and bGl 5-7; or PSA > 10-20 ng/ml and bGl < or = 7; high = PSA >
4-20 ng/ml and bGl > or = 8. Two-year PSA failure-free survival for surgically
managed and radiation-managed patients, respectively, were 98% vs. 92% (p = 0.45), 77% vs.
81% (p = 0.86), and 51% vs. 53% (p = 0.48) for patients at low, intermediate, and high
risk for post-therapy PSA failure. CONCLUSIONS: There was no statistical
difference in the 2-year PSA failure-free survival for potentially curable
patients managed definitively with surgery or radiation therapy when a retrospective
comparison stratifying for the pretreatment PSA and bGl was performed.
Stage T1-2 prostate cancer with pretreatment
prostate-specific antigen level < or = 10 ng/ml: radiation therapy or surgery?
Keyser D, Kupelian PA, Zippe CD, Levin HS, Klein EA. Int J Radiat Oncol
Biol Phys 1997 Jul 1;38(4):723-9
Department of Radiation Oncology, Cleveland Clinic Foundation, OH 44195, USA.
PURPOSE: To detect differences in biochemical failure rates by treatment modality
(radiation therapy or radical prostatectomy) in patients with early-stage prostate cancer
presenting with pretreatment prostatic-specific antigen (PSA) levels < or = 10.0 ng/ml.
METHODS AND MATERIALS: A total of 1467 consecutive patients with prostate carcinoma were
treated with either radiotherapy (RT) or radical prostatectomy (RP) between January 1987
and June 1996. Patients with the following were excluded from the present study: initial
PSA (iPSA) level > 10 ng/ml (n = 444), clinical Stage T3 disease (n = 73), adjuvant or
neoadjuvant treatment (n = 173), no available iPSA level (n = 31), no available biopsy
Gleason score (GS) (n = 33), incomplete pathologic information (n = 16), and no available
follow-up PSA levels (n = 90). The analysis was performed on 607 cases: 354 treated with
RP and 253 with RT (median dose 68.4 Gy). The outcome of interest was biochemical
relapse-free survival (bRFS), with biochemical relapse being defined as either a
detectable PSA level after RP or elevation in PSA levels of > or = 1.0 ng/ml above the
nadir after RT. Proportional hazards were used to analyze the effect of treatment modality
and confounding variables (i.e., age, stage, biopsy GS, iPSA levels) on treatment outcome.
RESULTS: Seventy-nine percent of patients (n = 478) had clinical Stage T1 or T2A disease
at presentation (RP vs. RT: 84% vs. 71%, p < 0.001). Twenty-one percent of patients (n
= 127) had iPSA levels < or = 4 ng/ml (RP vs. RT: 24% vs. 17%, p = 0.027). Seventy-six
percent of patients (n = 460) had biopsy GS < or = 6 (RP vs. RT: 79% vs. 71%, p =
0.014). The median follow-up time was 24 months (range 3-110). For the 607 patients, the
5-year bRFS rate was 76%. The 5-year RFS rates for RP versus RT were 76% versus
75%, respectively (p = 0.09). After adjustment for all confounding variables,
iPSA levels (p < 0.001) and biopsy GS (p = 0.001) were the only independent predictors
of relapse, whereas age, clinical stage, and treatment modality were not (p = 0.20; p =
0.09; and p = 0.10, respectively). CONCLUSION: In patients with clinical Stage
T1-2 prostate cancer and pretreatment PSA < or = 10 ng/ml, there is no difference in
biochemical failure rates between those treated with radiation and those treated with
surgery.
External beam radiotherapy versus radical
prostatectomy for clinical stage T1-2 prostate cancer: therapeutic implications of
stratification by pretreatment PSA levels and biopsy Gleason scores.
Kupelian P, Katcher J, Levin H, Zippe C, Suh J, Macklis R, Klein E. Cancer J
Sci Am 1997 Mar-Apr;3(2):78-87
Department of Radiation Oncology, Cleveland Clinic Foundation, OH 44195, USA.
PURPOSE: Prostate-specific antigen (PSA) has affected the management of prostate cancer by
allowing better case selection. The comparison between the two definitive treatment
modalities, radiotherapy (RT) and radical prostatectomy (RP), can now be made accurately
with respect to case selection and treatment outcome. PATIENTS AND METHODS: The charts of
787 patients with prostate carcinoma who were treated with either RP alone or RT alone
between 1987 and 1993 were reviewed. Patients with stage T3 disease, without pretreatment
PSA levels or biopsy Gleason scores (GS), with synchronous bladder cancers or receiving
adjuvant therapy, were excluded. Patients with less than 2 years' follow-up were also
excluded. Of the remaining 551 patients, 253 were treated with RT and 298 with RP. The
median pretreatment PSA level for RP patients was 8.1 versus 12.1 for the RT patients. The
median radiation dose was 68.4 Gy. Positive margins were reported in 49% after RP. The
median follow-up time was 42 months (range: 24 to 108). RESULTS: For the 551 patients, the
5-year biochemical relapse-free survival (bRFS) rate was 53%, with biochemical relapse
being defined as either a detectable PSA level after RP, or two consecutive rising PSA
levels after RT. All clinical relapses were associated with rising PSA levels. The 5-year
bRFS rates for RT versus RP were 43% versus 57%, respectively. Multivariate
time-to-failure analysis using the proportional hazards model for clinical parameters
showed pretreatment PSA level and biopsy Gleason scores to be the only independent
predictors of relapse. Clinical stage and treatment modality were not independent
predictors of failure. Using PSA and GS, two risk groups were defined: low risk
(PSA < or = 10.0 and GS < or = 6) and high risk (PSA > 10.0 or GS > or = 7).
The 5-year RFS rates for the low-versus high-risk groups were 81% versus 34%,
respectively. Forty-eight percent of RP patients were low-risk cases versus 33% of RT
patients. The rate of surgical margin involvement in RP patients was 39% in the low-risk
group versus 59% in the high-risk group. For low-risk patients, the 5-year RFS
rates for patients treated with RT versus RP were 81% versus 80%, respectively.
In this subgroup, the bRFS rates for patients with negative margins were identical to the
bRFS rates of patients treated with radiotherapy. However, patients with positive surgical
margins fared significantly worse. For high-risk patients, the 5-year RFS rates
for patients treated with RT versus RP were 26% versus 37%, respectively. In
this subgroup, there was a definite advantage to surgery if negative margins were
achieved: 5-year bRFS 62%, compared to 26% for RT and 21% for surgery with positive
margins. CONCLUSIONS: By using biochemical failure as an endpoint, more failures are
documented after RP or RT than previously suspected. However, case selection using
pretreatment PSA levels and biopsy GS can result in large differences in control rates.
Significantly more high-risk patients are treated with RT. By stratifying cases using PSA
and biopsy GS, treatment outcome is equivalent after either radiotherapy or surgery.
Further follow-up is needed to confirm these findings after 5 years. For low-risk cases,
there is no difference between radiotherapy and surgery, even when negative margins are
achieved. Positive surgical margins predict for poor outcome even in low-risk cases. Standard
radiotherapy alone should not be used for lesions with aggressive features.
The outcome in high-risk cases is better with surgery if negative margins are achieved.
For such high-risk patients, several new treatment approaches are currently being
investigated with either high-dose conformal radiotherapy with or without androgen
blockade, or neoadjuvant androgen blockade or radical prostatectomy.
A comparison of external beam radiation therapy
versus radical prostatectomy for patients with low risk prostate carcinoma diagnosed,
staged, and treated at a single institution.
Martinez AA, Gonzalez JA, Chung AK, Kestin LL, Balasubramaniam M, Diokno AC, Ziaja EL,
Brabbins DS, Vicini FA. Cancer 2000 Jan 15;88(2):425-32
Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, Michigan 48073,
USA.
BACKGROUND: The authors retrospectively reviewed their institution's long term experience
treating a group of comparably staged low risk prostate carcinoma patients with either
radical prostatectomy or external beam radiation therapy (RT) to determine whether the
method of treatment resulted in significant differences in biochemical control and/or
survival. METHODS: From January of 1987 through December of 1994, 382 patients (157 who
underwent radical prostatectomy and 225 who received external beam RT) were treated with
curative intent for localized prostate carcinoma at William Beaumont Hospital. All
patients had a pretreatment serum prostate specific antigen (PSA) level < or =10.0
ng/mL and a biopsy Gleason score </=6. Patients treated with RT received a
median dose of 66.6 gray (Gy) (range, 59.2-70.2 Gy) to the prostate. Patients treated
surgically underwent radical retropubic prostatectomy with a pelvic lymph node dissection.
For surgical patients, biochemical failure was defined as a detectable PSA level > or
=0.2 ng/mL at any time after prostatectomy. For RT patients, biochemical failure was
defined according to the American Society for Therapeutic Radiology and Oncology Consensus
Panel definition. Pretreatment PSA levels and Gleason scores were not significantly
different between patients treated with radical prostatectomy or RT. The median follow-up
in each treatment group was 5.5 years. RESULTS: The 7-year actuarial rates of
biochemical control and cause specific survival were not significantly different between
patients treated either with radical prostatectomy or RT (67% vs. 69% for biochemical
control and 99% vs. 97% for cause specific survival, respectively). A number
of clinical, pathologic, and treatment-related factors were analyzed for an association
with biochemical failure (i.e., age, pretreatment PSA, Gleason score, and treatment
modality). Only pretreatment PSA and Gleason score were significantly related to outcome
in both univariate and multivariate analyses. CONCLUSIONS: Low risk prostate carcinoma
patients with similar pretreatment PSA levels and biopsy Gleason scores treated at the
same institution with either radical prostatectomy or RT achieved similar 7-year rates of
biochemical control and cause specific survival, regardless of treatment technique. These
findings suggest that for patients with pretreatment PSA levels </=10 ng/mL and Gleason
scores </=6, conventional doses of external beam RT and radical retropubic
prostatectomy can be expected to produce comparable treatment results unaffected by age at
diagnosis. |
