Adverse effects of first-line treatments for localized prostate cancer
Posted Dec 22 2010 12:00am
Prospective data from a significant Spanish study provide us with additional insights into the short- and longer-term adverse effects of common types of invasive therapy for localized prostate cancer.
Pardo et al. have reported on 435 men treated in the Spanish Multicentric Study of Clinically Localized Prostate Cancer, and Evans has offered additional editorial comment on this paper. Although smaller, the study has similarities to the major study reported by Sanda et al. in 2008. However, Pardo et al. carefully excluded from their study any patients who received hormone therapy as a component of their first-line treatment, and they differentiated between men receiving nerve-sparing and non-nerve-sparing surgery.
Pardo et al. basically categorized their patients into four groups:
Those receiving nerve-sparing radical prostatectomy (Group A)
Those receiving non-nerve-sparing radical prostatectomy (Group B)
Those receiving three-dimensional conformal beam radiation therapy (Group C)
Those receiving brachytherapy (Group D)
The patients were all treated at one of 10 Spanish hospitals between 2003 and 2005, and the quality of life of all patients was assessed at baseline (before treatment) and at 1, 3, 6, 12, 24, and 36 months after treatment.
The results of this study can be summarized as follows:
Patients in Groups A and B were generally younger than those in Groups C and D.
Patients in Group D had lower risk characteristics than those in Groups A, B, and C.
Patients in Groups A and B tended to have an immediate decline in urinary continence and sexual function with partial recovery over time.
Patients in Groups C and D reported more problems with bowel function and with urinary irritative and obstructive symptoms during months 13 to 36 of follow-up compared to patients in Groups A and B.
For patients with no sexual problems at baseline
For men with mild to moderate sexual dysfunction at baseline
Pre-treatment urinary continence was preserved
Post-treatment urinary irritative/obstructive symptoms were greatest (at 35 percent) in men in Group D.
Among men with mild to moderate urinary irritative/obstructive symptoms at baseline, 64 percent of those in Group A had documentable improvement in their symptoms.
There were few reported bowel problems pre-treatment, but 23 percent of men in Group C reported bowel problems at 3 years of follow-up.
Approximately 20 percent of men overall reported adverse hormonal effects following treatment, with no noticeable difference between the treatment modalities.
The results reported by Pardo et al. have strong similarities to those reported previously by Sanda and his colleagues. The problem, of course, is that these outcomes are depressing from a quality of life point of view, and they don’t seem to us to reflect the way a majority of surgeons and radiation oncologists talk to their patients about the consequences of treatment before their therapy.
It is perhaps inevitable that physicians should “put the best possible face” on the outcomes of treatment. However, with the growing awareness that active surveillance is a sound option for many patients with localized disease, not telling patients that there is (for example) a 90 percent probability of significant loss of sexual function at 3 years post-surgery for any man with good sexual function pre-surgery is bordering on the unethical (unless you are one of the very few surgeons who has well-documented data suggesting better sexual function outcomes at 3 years).
Obviously we know nothing about the skill levels of the clinicians treating patients in this study as compared to those treating patients at the major prostate cancer centers in the Sanda et al. study. It would hardly be appropriate to try to compare the precise data from the two studies. What both studies show, however, is that there is a high level of long-term effects associated with the various invasive treatments widely applied for the first-line treatment of localized disease, and that these effects may well be more common than individual physicians tend to suggest when speaking with their patients.