In a nutshell
This study investigated the presence of the gene TMPRSS2-ERG in patients with metastatic castration-resistant prostate cancer on treatment outcome with taxane-based chemotherapy. Researchers reported that TMPRSS2-ERG, as identified by blood tests, is a reliable predictors of treatment success with taxane-based chemotherapy.
Some background
Chemotherapy with taxane-based agents, such as docetaxel (Taxotere), is a common treatment for metastatic castration-resistant prostate cancer (cancer that has spread despite hormonal therapy). In cases when men do not respond to taxane-based chemotherapy, alternative chemotherapy with cabazitaxel (Jevtana) is often required. Since chemotherapy is associated with various side effects, being able to predict whether taxane-based chemotherapy predicting treatment success early may reduce unnecessary adverse effects.
There is some evidence to suggest that the presence of the TMPRSS2-ERG gene in prostate cancer cells may afftect the response to taxane-based chemotherapy. Further studies are needed to establish a link between TMPRSS2-ERG and resistance to taxane-based chemotherapy.
Methods & findings
This study included 72 men with metastatic castration-resistant prostate cancer. 50 of these men were undergoing treatment with docetaxel, and 22 were undergoing treatment with cabazitaxel. Blood samples were collected from all men and compared to those of healthy volunteers without prostate cancer (used as a control).
No TMPRSS2-ERG was detected in the blood samples of the healthy volunteers. TMPRSS2-ERG was detected in 16% of men undergoing treatment with docetaxel, and in 22.7% of men undergoing treatment with cabazitaxel. Among docetaxel-treated patients, those positive for the TMPRSS2-ERG gene showed significantly lower response rate to docetaxel treatment (12.5% response rate), compared to men without the gene (68.3% response rate). No differences were noted between men with and without TMPRSS2-ERG in the response rate to cabazitaxel.
Imaging and blood tests of cancer progression showed significantly faster disease progression among TMPRSS2-ERG-positive men, regardless of treatment received.
The bottom line
The researchers concluded that the presence of the TMPRSS2-ERG gene was associated with poorer treatment response to taxane-based chemotherapy. TMPRSS2-ERG may, therefore, be a useful marker in treatment selection.
The fine print
Larger randomized trials are needed to confirm these preliminary results.
Published By :
European Urology
Date :
Feb 29, 2016
