PSA levels, prostate cancer risk, and diagnosis in the “real world”
Posted Jun 29 2010 12:00am
For all of the academic literature and the recommendations of guideline-generating organizations on testing, diagnosis, and management of prostate cancer, urologists out in community practice may show considerable variation in their clinical practice patterns.
Lawrentschuk et al. recently conducted a survey of the practice patterns of Canadian urologists with respect to the detection of prostate cancer. The primary focus of their survey was to assess those factors that were crucial to the decision to recommend that a patient undergo a transrectal ultrasound-guided prostate biopsy because of the patient’s potential risk for prostate cancer.
The survey apparently used case scenarios of patients with a variety of ages, family histories, ethnicities, and PSA levels, and the urologists were asked to indicate when they they would recommend a biopsy in each case scenario. All 360 active urologists who belong to the Canadian Urological Association were asked to participate in this online survey; apparently 125/360 urologists actually completed the questionnare, with the following results:
67 percent of respondents indicated men should be tested for prostate cancer starting at age 50-60.
27 percent indicated that testing should be initiated in men aged 40-50 years.
77 percent of the respondents would continue to test men of >75 years of age.
The abstract also gives two specific case examples:
In the first case, the patient is a 65-year-old male who has no known risk factors and a normal DRE.
In the second case, the patient is a 45-year-old man, also with no known risk factors and a normal DRE.
The decision to offer a patient a biopsy among this group of clinicians appears to be much more dependent upon younger age (odds ratio [OR], 4.3-20.6) and higher PSA level (OR, 4.4-34.9) compared to family history (OR, 3.3) or ethnicity (OR, 1.8), and this variation was highly statistically significant (P < 0.0001)
The authors conclude that among this group of community Canadian urologists patient age and PSA level appear the driving factors in recommendation of a biopsy, and that a significant proportion of these urologists would still not offer a biopsy at the traditional PSA cutoff of 4 ng/ml for men with no other known risk factors.
Two things are of great interest to The “New” Prostate Cancer InfoLink in trying to interpret this study.
The first is what appears to be a logical inconsistency between the relatively high proportion of Canadian urologists who would not recommend a biopsy for a 65-year-old man with a PSA of 4.5 ng/ml (44 percent) as compared to the very high percentage of Canadian urologists who would happily continue to offer PSA testing to men over the age of 75 (77 percent). Why is one giving PSA tests to asymptomatic 75-year-olds when one wouldn’t have been willing to biopsy them when they were 65?
The second is the apparent message to Canadian men that if they have significant concerns about a future risk for prostate cancer, based on such things as family history or ethnicity, they would be wise to start asking for PSA tests in their 40s rather than their 50s!