There is no broad agreement agreement (yet) across the prostate cancer community about acceptable “standard” criteria for eligibility for active surveillance as a form of first-line management of low-risk prostate cancer. On the other hand, there are two well-characterized and relatively broadly applied sets of criteria:
- Epstein and his colleagues at Johns Hopkins in Baltimore have defined what is probably the most rigorous and restrictive set of criteria, to include only those men who have clinical stage T1 or T2a disease; one or two positive biopsy cores (with < 50 percent of all cores positive for cancer); a PSA density of < 0.15; and a Gleason score of ≤ 6.
- By contrast, Klotz and his colleagues at the Sunnybrook center in Toronto have applied what is clearly a more expansive set of criteria, to include all men with a PSA ≤ 10 ng/ml (or < 15 ng/ml at age 70 years or more) and a Gleason score of ≤ 6 (or ≤ 3 + 4 = 7 at age 70 years or more).
Blázquez et al. have used data from a cohort of > 400 patients, all treated by radical prostatectomy at their institution in Brazil between August 2003 and December 2009, to evaluate the correlation between oncologic outcomes post-surgery and whether the patients met either the Epstein or the Klotz criteria for active surveillance.
Here are their core findings:
- The total cohort included 442 patients.
- 213/442 patients (48.2 percent) were diagnosed with low-risk prostate cancer and met criteria for evaluation.
- 76/213 patients (35.7 percent, or 17.1 percent of the entire cohort of 442 patients) met the Epstein criteria for active surveillance.
- 213/213 patients (100 percent, or 48.2 percent of the entire cohort of 442 patients) met the Klotz criteria for active surveillance.
- There were no statistically significant differences (P ≥ 0.4) in the pathological or clinical outcomes post-surgery of the patients meeting the Epstein as opposed to the Klotz criteria.
- For the patients meeting the Epstein criteria
- 7.9 percent had a pathologic stage of pT3.
- 22.4 percent had positive surgical margins.
- 5.3 percent exhibited biochemical recurrence within 3 years of surgery.
- For the patients meeting the Klotz criteria
- 10.8 percent had a pathologic stage of pT3.
- 28.3 percent had positive surgical margins.
- 5.6 percent exhibited biochemical recurrence within 3 years of surgery.
Clearly, in this series of patients, it would have been better to see a lower overall likelihood for positive surgical margins and longer follow-up data on risk for biochemical recurrence, but it is at least interesting that the differences between the outcomes for the two sets of patients was really rather small.
While it would be wrong to conclude from a retrospective analysis like this that one or other of the Klotz or the Epstein criteria were “right” as the definition of eligibility for active surveillance, what these data do offer is a degree of confidence that the more expansive Klotz criteria (that include at least some men with Gleason 3 + 4 = 7 disease) may be acceptable in the “real world” of clinical practice by comparison with the criteria deemed acceptable in more academic settings.