Neoadjuvant hormone therapy for radical prostate radiotherapy: bicalutamide monotherapy vs. luteinizing hormone-releasing hormone agonist monotherapy: a single-institution matched-pair analysis.
BACKGROUND
The purpose of this study was to compare the prostate-specific antigen (PSA) response to either neoadjuvant bicalutamide (BC) monotherapy or neoadjuvant luteinizing hormone-releasing hormone agonist (LHRHa) monotherapy and the subsequent effect on biochemical failure-free survival (BFFS) in men receiving radical radiotherapy (RT) for localized prostate cancer.


METHODS
This was a retrospective review of consecutive men treated with BC monotherapy before radical prostate RT who were individually case-matched to men treated with neoadjuvant LHRHa monotherapy. PSA kinetics and absolute pre-RT posthormone PSA (PRPH-PSA) level and subsequent BFFS were analyzed.


RESULTS
Sixty-five men treated with BC monotherapy with a median follow-up of 44 months were individually matched with 65 men treated with LHRHa with a median follow-up of 54 months. Statistically significant differences were noted between groups in the PRPH-PSA, with a mean of 2.9 ng/mL (0.1-11.2 ng/mL) for patients receiving BC treatment and 1.8 ng/mL (0.1-11.1 ng/mL) for patients receiving LHRHa treatment (P < .001). A PRPH-PSA of < 1.0 and < 0.1 ng/mL was seen in 16 (24.6%) and 2 (3%) of the patients receiving BC and 34 (52.3%) and 3 (4.6%) patients receiving LHRHa, respectively. There were no significant differences between groups in either PSA halving time or velocity. Phoenix biochemical failure occurred in 10 (15.4%) and 8 (12.3%) patients receiving BC and patients receiving LHRHa, respectively. Neither PRPH-PSA level nor PSA kinetics during the neoadjuvant period predict for subsequent BFFS at this duration of follow-up.


CONCLUSIONS
Although neoadjuvant BC therapy did not result in equivalent PRPH-PSA suppression when compared with neoadjuvant LHRHa alone, there was no difference in biochemical failure rates between cohorts at 50 months' median follow-up. Longer follow-up is required.
Department of Clinical Oncology, Northern Ireland Cancer Centre, Belfast City Hospital, Belfast, Northern Ireland.
Ursula
U
McGivern
Darren M
DM
Mitchell
Cliona
C
McDowell
Jolyne
J
O'Hare
Gemma
G
Corey
Joe M
JM
O'Sullivan
D000368:Aged; D000813:Anilides / Q000627:therapeutic use*; D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use*; D018572:Disease-Free Survival; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists / Q000031:analogs & derivatives* / Q000627:therapeutic use*; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009376:Neoplasms, Hormone-Dependent / Q000097:blood / Q000401:mortality / Q000628:therapy*; D009570:Nitriles / Q000627:therapeutic use*; D016016:Proportional Hazards Models; D017430:Prostate-Specific Antigen / Q000097:blood; D011471:Prostatic Neoplasms / Q000097:blood / Q000401:mortality / Q000628:therapy*; D020266:Radiotherapy, Conformal; D012189:Retrospective Studies; D014105:Tosyl Compounds / Q000627:therapeutic use*; D016896:Treatment Outcome
D000813:Anilides; D018931:Antineoplastic Agents, Hormonal; D009570:Nitriles; D014105:Tosyl Compounds; D007987:Gonadotropin-Releasing Hormone; C053541:bicalutamide; D017430:Prostate-Specific Antigen