BERKELEY, CA (UroToday.com) - Intuitively, more intense monitoring should find more cancer recurrences.
In this cohort of prostate cancer survivors diagnosed from 1995-2006 in a geographically defined, free-living population from Olmsted County, MN, we examined whether the intensity of prostate specific antigen (PSA) surveillance following definitive therapy, or watchful waiting for non-metastatic prostate cancer, varied according to different treatment groups and affected outcomes. In both univariate and multivariable models in those receiving radical prostatectomy or radiation therapy, the frequency of post-treatment PSA surveillance was not associated with differences of biochemical recurrence (BCR), prostate cancer-specific mortality, and all-cause mortality. These data suggest that greater intensity post-treatment PSA surveillance may not increase the ability to detect BCR, or confer improved survival.
| "Our results suggest that an evidence-based protocol for PSA monitoring following primary therapy may help lower health care costs related to prostate cancer..." |
Our findings suggest that more intense testing may not be causing overt harm since it does not seem to be causing over-diagnosis of BCR that may or may not ultimately influence prognosis. Higher intensity of PSA monitoring in prostate cancer survivors following primary therapy or those individuals who receive watchful waiting appears to have no demonstrable positive effect on their disease-specific or overall survival. Patients diagnosed with low-risk prostate cancer and treated with radical prostatectomy have minimal risk for BCR, and life-long PSA surveillance may be unnecessary.1 Furthermore, greater frequency of testing may have adverse effects on psychological parameters, such as worry and anxiety. This analysis was unable to assess those outcomes. Although we did not specifically measure anxiety, we speculate that while survivors may insist on the importance of getting a regular PSA, and physicians may use the test to allay patient anxiety, more intense utilization of PSA in the asymptomatic early years after definitive treatment may fuel rather than allay anxieties. Another inference from our results here relates to the increased costs attributable to healthcare. More specifically, prostate cancer represents a significant annual expenditure for Medicare, estimated at $7 billion.2 Our results suggest that an evidence-based protocol for PSA monitoring following primary therapy may help lower health care costs related to prostate cancer but further analyses would help establish those parameters with greater specificity.
Inferences from such analyses should be approached with caution. Failing to identify hypothesized associations between PSA testing frequency and biochemical recurrence as well as mortality, does not establish a sound basis for changes to clinical practice or evidence-based guidelines. Further, this study had limited power to detect change in mortality due to prostate cancer. These data are not prospective, so our ability to make causal inferences is limited. Another possible limitation of our study is shorter duration of follow-up. There is also a concern for ascertainment bias in that increased intensity of PSA testing following treatment (or diagnosis for watchful waiting) may influence the detection of biochemical recurrence. To best answer this clinical question about post-treatment PSA intensity, a randomized controlled trial of varying intensity of PSA monitoring following treatment in prostate cancer patients would best define the optimal post-treatment surveillance guidelines.
References:
- Tollefson MK, Blute ML, Rangel LJ, Karnes RJ, Frank I. Lifelong yearly prostate specific antigen surveillance is not necessary for low risk prostate cancer treated with radical prostatectomy. J Urol. 2010;184(3):925-929.
- Skolarus TA, Zhang Y, Miller DC, Wei JT, Hollenbeck BK. The economic burden of prostate cancer survivorship care. J Urol. 2010;184(2):532-538
Written by:
Mohammed Nabhan, MD as part of Beyond the Abstract on UroToday.com. This initiative offers a method of publishing for the professional urology community. Authors are given an opportunity to expand on the circumstances, limitations etc... of their research by referencing the published abstract.
Research Fellow
Knowledge and Evaluation Research Unit
Mayo Clinic
200 First Street SW
Rochester, MN 55905
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