Prostate cancer news reports: Tuesday, April 20, 2010

In today’s news reports we note new articles dealing with:

  • Biopsy protocols, patient selection, and focal therapy
  • Tertiary Gleason pattern 4/5 and risk for progression post-RP
  • Evolving data on the uses of bisphosphonates and denosumab
  • SKIs in treatment of advanced forms of prostate cancer

Tsivian et al. have reviewed data on patient selection for focal and hemiablative therapy. This team at Duke University has significant experience in this area, so their conclusion is of some significance. They state clearly that, “there is insufficient scientific evidence to propose a specific biopsy scheme that could fit every candidate, providing accurate characterization of the disease in the individual patient. Further research is necessary to establish solid selection protocols that would reliably identify appropriate candidates” for focal therapy.

Servoll et al. have demonstrated that — at least in a cohort of 151 Norwegian patients — a tertiary Gleason pattern of 4 or 5 is an independent predictor for biochemical relapse among patients with no pathological indication of primary or secondary Gleason pattern any higher than 3 who receive a radical prostatectomy as treatment for localized disease. These data would appear to confirm the importance of careful review of the pathology of all surgical specimens to identify the possible presence of tertiary Gleason pattern 4 or 5. The presence of either tertiary pattern clearly has long-term prognostic impact.

Neville-Webbe and Coleman have reviewed evolving data on the roles of bisphosphonates like zoledronate and the RANK-L inhibitor denosumab in the prevention of fractures, significant bone loss, and pain for men with advanced prostate cancer who are being treated with hormone therapy. They also discuss the evolution of data suggesting that bisphosphonate therapy may be able to prevent or delay the onset of metastatic disease.

Edwards has reviewed available data on the potential of Src and Src family kinase inhibitors (SKIs) like dasatinib and saracatinib in the treatment of advanced forms of prostate cancer. Some early Phase II data on saracatinib have been published, but it seems unclear whether this product will be advanced into Phase III trials. In the case of dasatinib (Sprycel), a randomized Phase III clinical trial is currently enrolling patients with castration-resistant prostate cancer into a trial comparing dasatinib + docetaxel to a placebo + docetaxel.

7 Responses

  1. OK. Hold the phone. The numbers in the [Norwegian] article make no sense. Am I reading it wrong? 56 is 38% of 148. However, 21 is 38% of 56 and 14% of 148. It is not 58% of either number. Also, 35 is 63% of 56, not 31%. It is 24% of 148. I don’t understand [Norwegian] math. Please explain. Also, with these numbers the people without tertiary patterns fared worse. Thanks.

  2. Chris:

    You may be over-complicating this. The abstract says that:

    • 56 patients altogether had a biochemical relapse.
    • 21 patients (58%) with a TGG pattern of 4 or 5 had a biochemical relapse (but it doesn’t say what the total number of patients was who had a TGG pattern of 4 or 5).
    • 35 patients (31%) without a TGG pattern of 4 or 5 had a biochemical relapse relapse (but it doesn’t tell us the total number of patients who did not have a TGG pattern of 4 or 5).

    So if 35 is 31% of the total number of patients who did not have a TGG pattern of 4 or 5, then a total of 112 patients did not have such a TGG pattern. This means that 148 — 112 did, i.e., 36 patients had a TGG pattern of 4 or 5, and 21/36 = 58%.

    If my interpretation is correct, then 58% of patients with a TGG of 4 or 5 progressed compared to just 31% of the patients without a TGG of 4 or 5. That’s nearly twice as many patients.

  3. Ok. That makes sense. I did not read it like that

  4. To put it another way:

    The total number FAILING (56 of 148) amounted 37.8% of those in the study.

    OF THOSE 56 FAILING PATIENTS equaling 37.8% of the total study group:

    The 21 failing patients who DID have a tertiary G-GRADE of 4 or 5 present in the surgically removed Prostate represents 62.5 % of ALL failures.

    The 35 failing patients who DID NOT have tertiary G-GRADE 4 or 5 present in the surgically removed Prostate represents 37.5 % of ALL failures.

    Obviously, the presence of either tertiary grades 4 or 5 in excised tissue had a SUBSTANTIAL impact (nearly double) on the statistical likelihood (the odds) of biochemical failure occurring in the patients in this study group. – (aka) az4peaks

  5. For the uninitiated “tertiary” means the third (3rd) in a series. Although, as such, it is not normally part of the actual Gleason SCORE, since 2006 the American College of Pathologists has recommended that the presence of any tertiary grade 5 at all always be mentioned in post-surgical pathology reports. The presence of tertiary grade 4 tissue is mentioned when it is higher than the highest Gleason grades contained in the Gleason SCORE. – (aka) az4peaks

  6. My next question would be how patients were in what group and what were failure rates by group? In other words: (a) 3 + 3 = 6 and TGG 0, 4, 5; (b) 3 + 4 = 7 and TGG 0, 5; (c) 4 + 3 = 7 and TGG 0, 5; (d) 4 + 4 = 8 and TGG 5.

  7. Chris:

    If you write to the authors they’ll probably be happy to send you a PDF of the actual paper, but I think you are “over-analyzing” data from much too small a study to get anything that would be meaningful at that degree of micro-analysis. To get anything meaningful at that level, my suspicion is that you would have to be looking at data from more like 560 failing patients than 56! (And therefore about 1,500 patients in total.)


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