Primary androgen deprivation therapy (PADT) has played an important role in the treatment of prostate cancer. We sought to identify factors of PSA progression in our series of patients with localized and locally advanced prostate cancer treated with PADT.
Six-hundred forty-nine patients with localized and locally advanced prostate cancer who received PADT from 1998 to 2005 by Nara Uro-Oncology Research Group were enrolled. Age, T classification, stage, PSA level at diagnosis, Gleason score, laterality of cancer detected by biopsy and seminal vesicle involvement (SVI) were adopted as parameters of PSA progression. Cox’s proportional hazards model was used to determine the predictive factors for PSA progression.
The median follow-up period and the median PSA level at diagnosis were 49 months and 15 ng/mL. The 5-year disease specific survival rate, overall survival rate and PSA progression-free survival (PFS) rate were 97.9 %, 91.9 % and 71.2 %, respectively. The univariate analysis showed that the PSA level at diagnosis, Gleason score, laterality of cancer detected by biopsy and SVI were independent predictive parameters of PSA-PFS. However, by multivariate analysis, only laterality of cancer detected by biopsy (unilateral vs. bilateral) was an independent predictive parameter of PSA-PFS (p = 0.034). The patients were classified into new risk groups base on three factors: PSA level at diagnosis, Gleason score, and laterality of cancer detected by biopsy. The PSA-PFS rates at 5-years in the low- (none or one factor), intermediate- (two factors) and high-risk (three factors) groups were 78.2 %, 62.5 % and 46.9 % (p < 0.001), respectively.
In localized or locally advanced prostate cancer patients who received PADT, laterality of cancer detected by biopsy was a significant predictor associated with a longer PSA-PFS. Our new risk grouping indicates the usefulness of PSA-PFS.