It is a well-known fact that there is a dose-response relationship for clinical control of localized prostate cancer. As a result of the promising high local control rates observed in different prospective dose-escalation studies in the USA, the CKVO 96-10 study was initiated in four cancer institutes in The Netherlands in 1997 investigating the tumor control and toxicity as a consequence of dose-escalation, comparing the standard dose of 68 Gy with the experimental dose of 78 Gy.
• The benefit of dose-escalation of RT for localized prostate cancer in terms of local control is undisputed.
• Patients with intermediate-risk prostate cancer and those with iPSA between 8 and 18 ug/L seem to benefit most from high-dose RT. However, from the current knowledge, neither low-risk nor high-risk patients could be safely excluded from high-dose RT because of the negative test of heterogeneity. Randomized trials are warranted to answer this important issue.
• The associated increased GI toxicity would be reduced by the recent implementation of image-guide intensity-modulated radiotherapy at our institute.
• Despite the increased GI toxicity seen in patients treated in the high-dose arm, dose-escalation did not appear to decrease QoL-scores significantly in these patients.
• Predictive models need to be developed in order to identify patients at high risk of toxicity from high-dose RT. The possible risks of complications and deterioration of QoL-scores must be carefully weighted against the benefit from dose-escalation.
• The optimal combination of HT and RT in high-risk prostate cancer patients are not yet well-defined