Blood test predicts prostate tumour resistance
A new blood test developed by researchers at the Technical University of Munich can detect drug resistance in patients with advanced prostate cancer (Eur Urol 2017. doi: 10.1016/j.eururo.2017.07.024).
The new blood test identifies AR-V7 RNA in the blood. AR-V7 is an androgen receptor variant that is resistant to enzalutamide and abiraterone. Currently AR-V7 can only be identified through more complex testing methods.
‘If we know in advance whether or not a tumour has developed cells with this receptor, we can provide treatment advice on an individual basis at an early stage – this can spare seriously-ill patients from undergoing an ineffective therapy,’ says Dr Matthias Heck, co-leader of the study.
Researchers analysed blood samples from 85 patients with advanced prostate cancer. Around one fifth of the patients had large amounts of AR-V7 RNA in their blood – an indication of large numbers of resistant tumour cells. These patients failed to respond to therapy with abiraterone and enzalutamide and had a poorer prognoses during the subsequent course of their illness. Their tumours returned more quickly and they had shorter survival times than other patients.