Choosing a strategy for dealing with prostate cancer with low-risk, clinically localized prostate cancer has been tough for patients. While there is a recent strong push toward active surveillance for such patients, surgery and radiation remain viable options.
There have been no clinical trials that have pitted these approaches against each other on an even basis, and that leaves doctors too in a quandary about which is really better both overall and for certain subgroups of patients. In the absence of solid trial evidence, the Prostate Cancer Results Study Group has published graphic evidence showing how individual studies of various treatments panned out in terms of success versus recurrence of cancer. Now another review group - the ICER - has published a report. I've just learned about it; it's dated December 22, 2008.
It seemed to me they are essentially saying that brachytherapy is probably the superior choice, overall, and that there are some doubts about proton therapy, both from a dose delivered standpoint and from a cost standpoint. However, the Evidence Review Group clearly does not try to rule any of these options in or out. They also prominently note that active surveillance is a good option for patients with clinically localized, low-risk prostate cancer, though I have not included such statements in the brief excerpts below.
Here are key details:
INSTITUTE FOR CLINICAL AND ECONOMIC REVIEW
FINAL APPRAISAL DOCUMENT
BRACHYTHERAPY & PROTON BEAM THERAPY
FOR TREATMENT OF
CLINICALLY-LOCALIZED, LOW-RISK PROSTATE CANCER
The abbreviation PBT means proton beam therapy and IMRT means Intensity Modulated Radiation Therapy. Brachytherapy is another name for therapy using radioactive seed implants or seeds temporarily inserted and then withdrawn. ERG means Evidence Review Group.
Here are a few key comments:
p. 13 "5) Despite the theoretical benefits of the dose distribution from protons vs. conventional radiation, there is still much uncertainty regarding the actual dose delivered to nontarget tissue, particularly with conventional proton scanning techniques and in a deep-seated target area like
p. 13 "The specific discussion of the assignment of ICER ratings for comparative clinical
effectiveness and for comparative value used two separate frameworks: 1) PBT vs. IMRT; and 2) brachytherapy vs. IMRT. There was unanimous consensus that, compared to IMRT, PBT should be rated “Insufficient” in comparative clinical effectiveness, due to the dearth of data on its benefits and harms in this patient population.... However, many members of the ERG felt that, because PBT is an expensive technology, some judgment of comparative value should be made in the review. Again, the consensus was unanimous in rating PBT as “Low Value” relative to
p. 13 "... The group was unanimous, however, in concluding with high confidence that
brachytherapy was at least “Comparable” to IMRT in terms of clinical effectiveness. While some ERG members (3/10) felt that increased patient convenience with brachytherapy translated into an “Incremental” clinical benefit, others felt that the effects of convenience would fade over time. Still, many in the group (6/10) felt that a rating of “Comparable” should be accompanied with note of a lower level of certainty that the evidence in fact suggests an incremental benefit with brachytherapy, due both to patient convenience and to the possibility of a better toxicity tradeoff. One member voted to rate brachytherapy as “Insufficient” to reflect the lack of comparative data. The group was unanimous in considering brachytherapy a “High Value” technology, whether compared to PBT or to IMRT."
These ICER documents are not that easy to read, but this 24 page "Executive Summary" probably has some good information for patients interested in these three therapies, as well as in active surveillance (AS). The latter is covered much more extensively in an ICER report on AS versus surgery.
For those of us who want to dig into the raw details of this review, ICER has published the entire study.