A long-term study from the Mayo Clinic reports a low incidence of complications (other than erectile dysfunction) following salvage radiotherapy for men with prostate cancer recurrence after an initial radical prostatectomy.
In this study, Peterson et al. report on data from 308 consecutive patients, all treated with salvage external beam radiation therapy (EBRT) at the Mayo Clinic between July 1986 and June 2003 as a consequence of a detectable PSA level after an initial radical prostatectomy. The median dose of radiation received by these patients was 64.8 Gy over several weeks.
The results of this study were as follows:
- Median post-radiation follow-up was 60 months (with a range from 1 day to 174 > 14 years).
- Late toxicity, i.e., adverse effects happening > 90 days after radiation was identified in 41/308 patients (13 percent).
- 12/308 patients (3.9 percent) had grade 2 urethral strictures and were treated with urethral dilation.
- 3/308 patients (1.0 percent) had grade 3 cystitis.
- 1/308 patients (0.3 percent) had a grade 4 rectal complication.
Many men with a rising PSA after surgery as an initial curative treatment for prostate cancer are very concerned about their potential risks for long-term side effects from radiation therapy, as indicated in a related media release from the Mayo Clinic. In particular, urinary leakage, is supposedly a concern of many patients who choose not to use radiation, but this was not observed to be a common side effect of treatment in this study. By contrast, radiation therapy is potentially curative for a high percentage of men with a rising PSA after radical prostatectomy, and what this study does is give a very clear perspective on the risk for significant, long-term, adverse effects of EBRT.
What is not reported in this study is the impact of surgery followed by EBRT on the sexual functionality of these patients. It is only appropriate to assume that most such patients will have very low levels of erectile function since both surgery and radiation have individual risk factors for erectile dysfunction, and therefore the combination of treatments is almost certainly going to affect sexual function in the majority of patients. However, loss of sexual function may be treatable in many patients for whom this is a significant concern.
Another matter that is not specifically addressed in this paper is whether any of the 308 patients received hormone therapy in combination with EBRT. Since this is not mentioned, we are assuming that these 308 patients did not have adjuvant hormone therapy, but were treated exclusively with radiation as second line treatment, but we have not been able to see the full text of the paper to confirm this.
The authors conclude their abstract by stating that their results show that < 1 percent of post-surgical, salvage EBRT patients exhibited a grade 3 or grade 4 complication by 5 years after the start of EBRT, and that “This treatment can be administered in a manner that results in a low likelihood of late complications.”
In the associated media release, one of the paper’s authors is reported to have said, correctly, that “Improved techniques in the administration of salvage external beam radiotherapy since the study began in 1987 likely would mean the rate of side effects today, compared to those in the study, would be much lower,” and that “We can do a better job today with delivering radiation precisely where we want to, while minimizing dose to surrounding normal tissues.” This would imply that men receiving timely salvage radiation therapy today in response to a rising PSA after radical surgery are at even less risk for long-term adverse effects of radiation and have a greater chance that the radiation would be curative.