| Abstract: |
The combination of neoadjuvant hormone therapy (NHT) with radiotherapy (XRT) appears to be efficacious in experimental models of prostate cancer, These studies have demonstrated the importance of timing with regard to NHT for the combination to be most effective. However, studies using human prostate cancer cells demonstrate the need for mitogenic stimuli in order for radiation-induced death to occur, as the cells undergo post-mitotic apoptosis in response to XRT, Paradoxically, NHT may protect cells from radiation-induced death by attenuating cell-cycle progression. The clinical studies to date have shown improvements in local progression, metastases progression, and prostate specific antigen (PSA) disease-free survival. As there were no NHT controls in these studies, it is possible these effects were attributable to androgen deprivation and not the combination, as was demonstrated in the MRCS study, Although the EORTC study did show an improvement in patient survival with combination therapy, this finding has not been validated by other studies, which showed no survival benefit. As the follow-up in these studies has been short, forthcoming updates are necessary to determine the actual benefits of combination therapy for prostate cancer. |
