THE "NEW" PROSTATE CANCER INFOLINK

Loeb et al. have published additional information in support of their argument that prostate-specific antigen velocity (PSAV) ”could be useful in treatment decision-making and in assessing the likelihood of long-term cancer control in men with prostate cancer.” As Loeb et al. also note, “Conflicting evidence has been reported on the association of [PSAV] with Gleason score in prostate needle biopsy specimens.” 

It is well understood that the biopsy Gleason score and the true (pathologic, post-surgical) Gleason score are important prognostic indicators for men with prostate cancer, and, in modern practice, they frequently affect first-line and follow-up treatment decisions. The unanswered question, as posed by Vickers and others, is whether the PSAV adds additional knowledge to what we know about patient risk when we already know the PSA level, the biopsy (preoperative) Gleason score, and the clinical stage. The current paper does not resolve that question. It does, however, add to our knowledge.

The relationship between preoperative PSAV and pathologic Gleason score in the final radical prostatectomy specimen has never been formally demonstrated. In this study, Loeb et al. collated data on PSAV and pathologoca Gleason score from a total of 1,049 men treated with radical prostatectomy. They then performed statistical analyses to examine the relationship between the preoperative PSAV, pathologic Gleason score, and other adverse tumor features.

Their results were as follows:

• Median preoperative PSAV was 0.84, 0.97, and 1.39 ng/mL/yr in men with pathologic Gleason scores of 6, 7, and 8-10, respectively (P = 0.05).
• A PSAV > 2 ng/mL/yr was significantly associated with a pathologic Gleason score of ≥ 7.
• The preoperative PSAV was significantly lower in men with pathologically proven, organ-confined disease (0.82 vs 1.17 ng/mL/yr, respectively, P = 0.002).

While these results clearly demonstrate that there is an association between PSAV and pathologic Gleason score as markers for prostate cancer aggressiveness, and that the preoperative PSAV was a significant independent predictor of the pathologic Gleason score and non-organ-confined disease in the radical prostatectomy specimen, they do not resolve the question posted by Vickers because they do not address the biopsy (preoperative) Gleason score and related matters.

We are tempted to wonder why Loeb et al. did not include the preoperative Gleason scores, the PSA values, and the clinical staging data in carrying out this analysis. Such data was almost certainly available for the vast majority of these 1,049 patients. If the addition of the PSAV data to the PSA, the preoperative Gleason score, and the clinical stage had demonstrated a closer correlation with the pathologic, postoperative Gleason score, and the pathologic stage of these patients (even in such a retrospective analysis), it would at least have suggested that Vickers and his colleagues could be wrong. As it is, we appear to be no nearer to resolving this issue.

Filed under: Diagnosis, Management, Treatment