Whole-pelvis radiotherapy in combination with interstitial brachytherapy: does coverage of the pelvic lymph nodes improve treatment outcome in high-risk prostate cancer?
OBJECTIVE
To compare biochemical progression-free survival (bPFS), cause-specific survival (CSS), and overall survival (OS) rates among high-risk prostate cancer patients treated with brachytherapy and supplemental external beam radiation (EBRT) using either a mini-pelvis (MP) or a whole-pelvis (WP) field.


METHODS
From May 1995 to October 2005, 186 high-risk prostate cancer patients were treated with brachytherapy and EBRT with or without androgen-deprivation therapy (ADT). High-risk prostate cancer was defined as a Gleason score of > or =8 and/or a prostate-specific antigen (PSA) concentration of > or =20 ng/ml.


RESULTS
With a median follow-up of 6.7 years, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 91.7% vs. 84.4% (p = 0.126), 95.5% vs. 92.6% (p = 0.515), and 79.5% vs. 67.1% (p = 0.721), respectively. Among those patients who received ADT, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 93.6% vs. 90.1% (p = 0.413), 94.2% vs. 96.0% (p = 0.927), and 73.7% vs. 70.2% (p = 0.030), respectively. Among those patients who did not receive ADT, the 10-year bPFS, CSS, and OS rates for the WP vs. the MP arms were 82.4% vs. 75.0% (p = 0.639), 100% vs. 88% (p = 0.198), and 87.5% vs. 58.8% (p = 0.030), respectively. Based on multivariate analysis, none of the evaluated parameters predicted for CSS, while bPFS was best predicted by ADT and percent positive biopsy results. OS was best predicted by age and percent positive biopsy results.


CONCLUSIONS
For high-risk prostate cancer patients receiving brachytherapy, there is a nonsignificant trend toward improved bPFS, CSS, and OS rates when brachytherapy is given with WPRT. This trend is most apparent among ADT-naïve patients, for whom a significant improvement in OS was observed.
Bittner
Nathan
N
Tacoma/Valley Radiation Oncology Centers, Tacoma, Washington, USA.
Merrick
Gregory S
GS
Wallner
Kent E
KE
Butler
Wayne M
WM
Galbreath
Robert
R
Adamovich
Edward
E
D000368:Aged; D000704:Analysis of Variance; D001918:Brachytherapy / Q000379:methods*; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D006801:Humans; D015182:Lymphatic Irradiation / Q000379:methods*; D008297:Male; D010388:Pelvis; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000401:mortality / Q000532:radiotherapy*; D012189:Retrospective Studies; D016896:Treatment Outcome
D017430:Prostate-Specific Antigen