Measuring time to biochemical failure in the TROG 96.01 trial: when should the clock start ticking?
OBJECTIVE
We sought to determine whether short-term neoadjuvant androgen deprivation (STAD) duration influences the optimal time point from which Phoenix fail (time to biochemical failure; TTBF) should be measured.


METHODS
In the Trans-Tasman Radiation Oncology Group 96.01 trial, men with locally advanced prostate cancer were randomized to 3 or 6 months STAD before and during prostatic irradiation (XRT) or to XRT alone. The prognostic value of TTBF measured from the end of radiation (ERT) and randomization were compared using Cox models.


RESULTS
Between 1996 and 2000, 802 eligible patients were randomized. In 436 men with Phoenix failure, TTBF measured from randomization was a powerful predictor of prostate cancer-specific survival and marginally more accurate than TTBF measured from ERT in Cox models. Insufficient data were available to confirm that TTBF measured from testosterone recovery may also be a suitable option.


CONCLUSIONS
TTBF measured from randomization (commencement of therapy) performed well in this trial dataset and will be a convenient option if this finding holds in other datasets that include long-term androgen deprivation data.
Denham
James W
JW
School of Medicine and Public Health, University of Newcastle, New South Wales, Australia. Jim.Denham@newcastle.edu.au
Steigler
Allison
A
Kumar
Mahesh
M
Lamb
David S
DS
Joseph
David
D
Spry
Nigel A
NA
Tai
Keen-Hun
KH
Atkinson
Chris
C
Turner
Sandra
S
Greer
Peter B
PB
Gleeson
Paul S
PS
D'Este
Catherine
C
D000368:Aged; D000369:Aged, 80 and over; D000726:Androgen Antagonists / Q000627:therapeutic use*; D018572:Disease-Free Survival; D006801:Humans; D008297:Male; D008875:Middle Aged; D020360:Neoadjuvant Therapy; D009364:Neoplasm Recurrence, Local / Q000097:blood; D010173:Palpation; D016016:Proportional Hazards Models; D017430:Prostate-Specific Antigen / Q000097:blood*; D011471:Prostatic Neoplasms / Q000097:blood* / Q000188:drug therapy / Q000401:mortality / Q000532:radiotherapy; D013739:Testosterone / Q000097:blood; D013997:Time Factors
D000726:Androgen Antagonists; D013739:Testosterone; D017430:Prostate-Specific Antigen