Dear Editor

The TMPRSS2-ERG has been described in several prostate cancer patients' cohorts. The article by Ashish et al. describes the frequency of this fusion in another patient cohort. It further demonstrates that the frequency of TMPRSS2-ERG is increased in moderate to poorly differentiated tumors. We would like to congratulate the authors on their interesting study and advocate that more work still has to be carried out to investigate and characterize the true frequency and association of TMPRSS2-ERG gene fusion in prostate cancer. Earlier reports have generated conflicting results about the association of the TMPRSS2-ERG with Gleason score. It has been demonstrated earlier that the rate of fusion positive tumours is actually lower in the poorly differentiated tumours.¹ This latest finding was confirmed by our own study (data not published). These results should be further confirmed in larger and multiple cohorts as we investigate the TMPRSS2-ERG gene fusion as a biomarker of aggressive prostate cancer.

References:
1. Tu et al Modern Pathology (2007) 20, 921-928