@copyman I always look at the inverse for these. If your treatment has an 80% chance of 10 years no recurrence going to 88% is an additional 10%. However, looked at from chance of a recurrence the 20% went down to 12% for a 40% decrease. This can be applied to recurrence, metastases, death or any other success statistic available. Sometimes even these numbers get very small especially with extended (> 1 year) ADT for localized prostate cancer when the total effect on the body is considered (all causes mortality).