Methylgreat.

While we’re on the biomarker kick, let’s explore better ways than PSA alone to determine when to throw in the towel on docetaxel for metastatic castrate-sensitive prostate cancer (mCSPC). Enter GSTP1, a gene which is methylated in >90% of prostate cancers. In fact, it is more specific for prostate cancer that PSA since mGSTP1 really shouldn’t be detected in serum at all otherwise. This secondary analysis of the phase 3 SYNERGY trial assessed serum mGSTP1 levels at baseline and after docetaxel among 600 enrolled men with mCSPC. Serum mGSTP1 was detectable in just over 80% of men at baseline, and starting out undetectable was independently associated with lower risk of death (HR 0.4). What’s more, mGSTP1 became undetectable in half of these men after only two cycles of docetaxel which was also independently associated with lower risk of death (HR 0.36). TBL: Serum mGSTP1 may give PSA a run for its money in the risk-stratification and treatment algorithms for mCSPC. | Mahon, Eur Urol 2019