THE "NEW" PROSTATE CANCER INFOLINK

A new paper to be presented at the Genitourinary Prostate Cancer Symposium has proposed development of a standardized method to “score” whether patients are suitable candidates for initial management on active surveillance.

This poster by Scardino et al. (abstract no. 84; “Application of active surveillance threshold to series of samples submitted for commercial testing”) suggests that it may be possible to combine data from commercial cell cycle progression (CCP) testing with the patients’ CAPRA scores to develop a “combined clinical CCP risk” or CCR score. The CCR score can then be used to define and qualify whether patients are or are not good candidates for initial management on active surveillance.

The development of such a numeric scoring system to evaluate which patients are and aren’t good candidates for initial management on active surveillance would, theoretically, be very helpful to physicians and patients in determining which patients ought, initially, to be managed on active surveillance, and it would remove the problem about personal biases regarding who should be advised that active surveillance is or is not an appropriate form of initial management. However, validating the accuracy of such a system will be complicated and may take time.

Scardino et al. report data from a cohort of nearly 8,000 patients, all of whom had their CCP score calculated at Myriad Genetics based on prostate biopsy samples submitted from multiple different academic centers. (The CCP score is determined using the Prolaris test from the evaluation of RNA expression of 31 CCP genes normalized to 15 housekeeping genes.) Relevant clinicopathological data for each patient was also submitted for each patient’s biopsy specimens. By combining the patients’ CCP scores and their CAPRA scores, a CCR score was defined for each patient, and a threshold CCR score was used to define whether a patient was or was not a good candidate for active surveillance.

Scardino et al report the following:

• 4,758/7,881 patients (60.4 percent) qualified as appropriate for active surveillance based on their CCR score.
• Just 2,545/7,881 patients (32.3 percent) would have qualified as appropriate for active surveillance based exclusively on their clinicopathological data (i.e., having a Gleason score of ≤ 3 + 4 = 7, a PSA level < 10, a clinical stage ≤ T2a, and < 25 percent of their biopsy cores positive for cancer).

A table associated with this abstract gives the relevant clinicopathological data for all the 4,758 patients who were said to qualify for active surveillance based on their CCR scores.

The key question, of course, is what the outcomes of these patients would have been over time if they had been managed initially on active surveillance. In other words, what is an acceptable outcome for first-line management on active surveillance. Clearly it is not as simple as lifetime deferral of any type of invasive treatment (although that is the best possible outcome from active surveillance). So what is an acceptable outcome? Might it be 5-year deferral of treatment? Or what about just 2-year deferral? We really don’t have a good answer to this yet. And Scardino et al. do not give us any detail in their abstract about the CCR cut-point score.

Scardino et al. conclude simply that their data show the following:

• 60.4 percent of the commercially tested patients qualified for active surveillance, nearly half of whom would not have qualified based on clinicopathological characteristics.
• The CCR score provides significant prognostic information at time of diagnosis for those men who want to consider deferral of treatment.

We need to have more information before such a method for determination of eligibility for active surveillance could possibly be validated and recommended. … But the concept does seem like a good idea, at least in theory. Of course the developers of other genetic/genomic tests will likely argue that their tests are just as good (or better) than the Prolaris test in the assessment of risk for aggressive forms of prostate cancer. That’s another fly in the ointment of how to move forward, because we have no data comparing results of the Prolaris test to other, similar tests as prognostic markers of risk for progressive prostate cancer.

Filed under: Diagnosis, Management, Risk | Tagged: active, CAPRA, CCP, CCR, prognosis, PROLARIS, surveillance |