Optimizing patient selection for dose escalation techniques using the prostate-specific antigen level, biopsy gleason score, and clinical T-stage.
OBJECTIVE
Ideal candidates for 3D dose escalation conformal radiation or external beam + implant therapy are identified on the basis of the prostate-specific antigen (PSA) level, biopsy Gleason score, and the 1992 American Joint Commission Cancer (AJCC) clinical T-stage.


METHODS
The pathologic findings of 1742 men with clinical stage T1c,2 prostate cancer managed with a radical prostatectomy (RP) between 1990 and 1998 were subjected to a logistic regression multivariable analysis. The endpoints examined included pathologic organ-confined (OC), specimen-confined (SC), and margin (M) or seminal vesicle (SV) positive disease. SC disease was defined as extracapsular extension (ECE) with a negative surgical margin. The clinical factors tested included PSA level, biopsy Gleason score, and the 1992 AJCC clinical T-stage. PSA failure-free (bNED) survival was calculated according to the method of Kaplan and Meier.


RESULTS
Significant negative predictors of pathologic OC-disease or positive predictors of M+ or SV+ disease included a PSA > 10 ng/ml (p<0.0001), biopsy Gleason score < or =7 (p< or =0.0004), and > or =T2b disease (p< or =0.03). Only biopsy Gleason score 7 (p = 0.0006) and PSA 10-15 ng/ml (p = 0.04) were significant predictors of SC disease. The estimates of 5-year bNED survival were 80%, 62%, and 35% (p<0.0001) for patients having a low, intermediate, or high likelihood of having M+ or SV+ disease respectively.


CONCLUSIONS
Patients most likely to derive a survival benefit from the improved local control possible using dose escalation techniques were those who had both a low risk of having occult micrometastatic disease (<25% M+ or SV+) and a reasonable likelihood of remaining disease-free after RP (>50% 5-year bNED). These patients included those having T1c, 2a, PSA > 10-15 ng/ml, and biopsy Gleason < or =6 or T1c, 2a, 2b, PSA < or =10 ng/ml, and biopsy Gleason < or =7 prostate cancer.
D'Amico
A V
AV
Joint Center for Radiation Therapy, Harvard Medical School, Boston, MA 02215. USA. adamico@jcrt.harvard.edu
Whittington
R
R
Malkowicz
S B
SB
Schultz
D
D
Renshaw
A A
AA
Tomaszewski
J E
JE
Richie
J P
JP
Wein
A
A
D001706:Biopsy; D018572:Disease-Free Survival; D006801:Humans; D008197:Lymph Node Excision; D008297:Male; D009367:Neoplasm Staging; D018365:Neoplasm, Residual; D018579:Patient Selection; D010388:Pelvis; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood / Q000473:pathology / Q000532:radiotherapy*; D020266:Radiotherapy, Conformal / Q000379:methods*; D012044:Regression Analysis
D017430:Prostate-Specific Antigen