A study performed in Finland evaluating adjuvant radiotherapy following radical prostatectomy (RP) for prostate cancer that has positive margins or extracapsular extension found that adjuvant therapy extends biochemical recurrence-free survival compared to RP alone.

The study enrolled 250 men with pT2 prostate tumors and positive surgical margins or pT3aN0M0 cancer without seminal vesicle invasion. One hundred and twenty-one (121) men were given adjuvant radiotherapy (5 men from the randomization process declined post-RP radiotherapy), and 124 only had RP (observation arm). The radiation dose in the adjuvant group was 66.6 Gy given in 37 fractions.

The median follow-up time for men who were alive at the end of follow-up was 9.3 years in the adjuvant radiation group compared with 8.6 years in the observation arm.

The 10-year biochemical recurrence-free survival rate was 82% in the adjuvant radiation group compared with 61% in the RP only arm.

The study concluded that the adjuvant group had a significant 74% decreased risk of biochemical recurrence compared within who had only surgery.

The 10-year overall survival rates did not differ significantly between the adjuvant and observation groups (92% and 87%, respectively). Only two men died from prostate cancer, 1 in each group. The 10-year prostate cancer-specific survival rate was 99% in both groups.

Greetta Hackman, MD, of the University of Helsinki, and collaborators reported in European Urology