Prostate Cancer Treatment (PDQ®): Treatment - Health Professional Information [NCI] - Stage I Prostate Cancer Treatment
Consideration may also be given to postoperative radiation therapy (PORT) for patients who are found to have seminal vesicle invasion by tumor at the time of prostatectomy or who have a detectable level of PSA more than 3 weeks after surgery.[10,11,12] Because duration of follow-up in available studies is still relatively short, the value of PORT is yet to be determined; however, PORT does reduce local recurrence. Careful treatment planning is necessary to avoid morbidity.
Evidence (radical prostatectomy followed by radiation therapy):
- In a randomized trial of 425 men with pathologic T3, N0, and M0 disease, postsurgical EBRT (60–64 Gy to the prostatic fossa over 30–32 fractions) was compared with observation.[Level of evidence: 1iiA]
- The primary endpoint, metastasis-free survival, could be affected by serial PSA monitoring and resulting metastatic work-up for PSA increase. This could have biased the primary endpoint in favor of radiation therapy, which was associated with a lower rate of PSA rise. Nevertheless, metastasis-free survival was not statistically different between the two study arms (P = .06). After a median follow-up of about 10.6 years, the overall median survival was 14.7 years in the radiation therapy group versus 13.8 years in the observation group (P = .16).
- Although the overall survival rates were not statistically different, complication rates were substantially higher in the radiation therapy group: overall complications were 23.8% versus 11.9%, rectal complications were 3.3% versus 0%, and urethral stricture was 17.8% versus 9.5%.
- After a median follow-up of about 12.5 years, however, OS was better in the radiation therapy arm; hazard ratio (HR)death of 0.72 (95% confidence interval [CI], 0.55–0.96; P = .023). The 10-year estimated survival rates were 74% in the radiation therapy arm and 66% in the control arm. The 10-year estimated metastasis-free survivals were 73% and 65% (P = .016).[Level of evidence: 1iiA]
- Another randomized trial came to a different conclusion with respect to the effect of postoperative radiation therapy on OS. [Level of evidence: 1iiA]. In the European Organization for Research and Treatment of Cancer (EORTC) trial (EORTC 22911 [NCT00002511]), 1,005 men aged 75 years and younger with clinical T0 to T3 prostate cancer were randomly assigned after prostatectomy to receive postoperative radiation (60 Gy) or observation, with subsequent therapy delayed until the occurrence of either biochemical or clinical relapse. The recommended treatment for local recurrence was radiation.
- With a median follow-up of 10.6 years (up to 16.6 years), the biochemical progression-free survival rates were higher in the observation study arm (60.6% vs. 41.1%; HR, 0.49; 95% CI, 0.41–0.59; P < .0001). Locoregional relapse rates were 8.4% versus 17.3% in favor of immediate radiation (HR, 0.45; 95% CI, 0.32–0.68; P < .0001).
- However, the large differences in biochemical relapse-free survival and local recurrence did not translate into an advantage in either distant metastasis (11.0% vs. 11.3%; HR, 0.99; 95% CI, 0.67–1.44; P = .94) or in OS (76.9% with immediate radiation vs. 80.7% with observation; HR, 1.18; 95% CI, 0.91–1.53; P = .2). Nor was there a difference in prostate cancer-specific mortality (3.9% vs. 5.2%; HR, 0.78; 95% CI, 0.46–1.33; P = .34)
- The 10-year cumulative risk of severe (grade 3) late toxicity in the immediate radiation study group was 5.3% versus 2.5% in the observation group (P = .052). Late adverse effects of any grade were also higher in the immediate radiation group (70.8% vs. 59.7%; P = .001).