Martin NE et al. – A biopsy Gleason score of 8–10 was associated with a shorter period of testosterone suppression following 6 months of combined androgen blockade and radiation therapy. These data are consistent with the hypothesis that a factor released from high–grade prostate cancer cells may impact on testosterone production.Methods
- The study cohort consisted of 221 men with PCa treated with RT and 6 months of CAB between 1996 and 2005.
- The authors defined the duration of testosterone suppression as the time between the last day of CAB and the date the testosterone returned to ≥ 252 ng/dL.
- They used Cox regression multivariable analysis to relate biopsy Gleason score to duration of testosterone suppression following cessation of CAB.
- A biopsy Gleason score of 8-10 had an adjusted hazard ratio (AHR) of 1.56 (95% confidence interval [CI] 1.04, 2.34; P= 0.03) for a shorter time to testosterone normalization relative to Gleason 6.
- Specifically, the 51 men with biopsy Gleason score of 8–10 had a median time to testosterone normalization of 17.0 months compared with 22.1 months and 23.8 months for those with biopsy Gleason ≤ 6 and 7, respectively.
- Increasing age was significantly associated with a longer duration of testosterone suppression (AHR of 0.95 [95% CI 0.92, 0.97; P < 0.001]) as was a higher baseline PSA (AHR 0.82 [95% CI 0.69, 0.97; P= 0.02]).