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Medical Forum / Diseases and Disorders / Prostate Cancer / April 2008Androgen deprivation for Stage 3. Research results questioned.
http://www.sciencedaily.com/releases/2008/04/080421072217.htm American Cancer Society (2008, April 23). Inaccuracies Revealed In Studies Of Cancer Treatment. ScienceDaily. Retrieved April 26, 2008, from http://www.sciencedaily.com /releases/2008/04/080421072217.htm A new study published in the Cancer, a peer-reviewed journal of the American Cancer Society, concludes that observational studies which compare outcomes of different cancer therapies, may produce results which are questionable. EXTRACT: .........To determine the accuracy of observational studies on cancer treatments, Dr. Sharon H. Giordano of the University of Texas MD Anderson Cancer Center in Houston and her colleagues compared the effectiveness of different cancer therapies in terms of prolonging survival in patients, using data from the SEER registry. They presented several examples, including re-analyses of previously published data. In all cases, they came up with improbable results, indicating how easy it is to generate questionable results when conducting an observational study. In their first analysis, the researchers looked at data on a hormone therapy called androgen deprivation in men with stage III prostate cancer. Randomized clinical trials have shown that androgen deprivation can improve survival in these patients. When the investigators analyzed data from the SEER registry of more than 5,000 men, they found that men treated with androgen deprivation actually had a higher risk of death from prostate cancer than men who did not receive the therapy./ .... Article continues.... Best wishes to all MikeHi On Apr 26, 12:56 pm, Mik...@anon.co.uk wrote: > http://www.sciencedaily.com/releases/2008/04/080421072217.htm > [quoted text clipped - 31 lines] > > MikeHi Mike, This sounds interesting, but one obvious question must be asked. Did the men who did not receive androgen deprivation have exactly the same spread of prostate cancer as those men who did receive the treatment, i.e. the same starting point? If so, were the men randomly assigned to either receive androgen deprivation or not? If not, then it is quite possible that androgen deprivation was only used for those men who were close to dying, so of course their rate of death would be higher than for those men who never received the treatment because their disease never progressed to the point where androgen deprivation was considered necessary. Ed Friedman On April 26, MikeHi wrote, in pertinent part: > A new study published in the Cancer, a peer-reviewed journal of the > American Cancer Society, concludes that observational studies which > compare outcomes of different cancer therapies, may produce results > which are questionable. For those who wish to see what the abstract actually says, see Giordano SH, et al., "Limits of observational data in determining outcomes from cancer therapy." Pub Med ID 18428196. Pub Med is at www.pubmed.gov It is a service of the US National Library of Medicine. It is well to note that this was a statistical, not clinical, study and that about 10% of the cases were colon cancer, not PCa. Here are the *improbable* results: "In all comparisons, the observational data produced improbable results. For example, when evaluating outcomes of men who were treated with and without androgen deprivation for locally advanced prostate cancer, men who underwent androgen deprivation had higher prostate cancer mortality (hazard ratio, 1.5; 95% confidence interval, 1.29-1.92) DESPITE CLINICAL TRIAL EVIDENCE that this treatment improves cancer mortality." (emphasis added) In short, it's a report of a statistical anomaly, NOT a clinical result. I do wish that Mike had included that information for two reasons: (a) it would not frighten men who are on ADT with information that is untrue, and (b) writing selfishly, I would not have had to take the time to run down the truth. I'll now repeat my previous rants: Never never never trust what some reporter claims about these matters (or much of anything else, for that matter, but that's for another day and forum). Always always always seek out the primary source of information. This present matter is just the latest in Bog knows how many similar cases where the reporter got it wrong. Regards, Steve J "Digressions, objections, delight in mockery, carefree mistrust are signs of health; everything unconditional belongs in pathology." --Friedrich Nietzsche Hi Ed: Steve (see below) has given another URL where we can presumable see the answer to your questions - and as I am a bit shell-shocked -arrgh - I shan't begin to summarise what you might find there. Meanwhile waiting for your table to guide us in assessing what's what. Hi Steve I am poking my head out of my air-raid shelter where deep instincts from long-ago direct me to proceed with all due haste when stuff starts showering on my head. In the good old days one knew why the guy up there with his finger on the button was doing what he was doing. So you couldn't really feel aggrieved at the noise and thunder. But, hey, I'm aggrieved this time! Steve -I think this is unwitting friendly fire. And that is said with the utmost respect to one of the posters I much rely on to inform my current fight. To divert a moment; when I first saw the study I laughed aloud. Because it summed up for me my feelings about the whole business of PCa research - whether I do it, or I read someone else has done it, or I listen to Pods or watch DVDs of top experts engaged in it. It's a field where statistics are a bunch of figures looking for an argument. But sometimes, it seems, not only figures looking for arguments? As I come up for air I'm still trying to work out how on earth I came into your sights? I did not produce the report. I did not endorse it one way or the other. I gave an extract so that the NG guys could judge whether it was for them. If so, they would, I assumed, click on the URL and see for themselves. You wrote: >On April 26, MikeHi wrote, in pertinent part: > >> A new study published in the Cancer, a peer-reviewed journal of the >> American Cancer Society, concludes that observational studies which >> compare outcomes of different cancer therapies, may produce results >> which are questionable. You then comment >For those who wish to see what the abstract actually says, see..... >Pub Med ID 18428196. Pub Med is at www.pubmed.gov What it "actually" says?? This is the opening paragraph of the report for which I gave the URL. It actually says: "Certain biases may exist in observational studies that compare outcomes of different cancer therapies, making the results questionable." That is "actually" different in any sense to what I wrote? Was this para from Science Daily in error in any way? >It is well to note that this was a statistical, not clinical, study and >that about 10% of the cases were colon cancer, not PCa. I quoted only the PCA para -for reasonably obvious reasons >Here are the *improbable* results: "In all comparisons, the >observational data produced improbable results. For example, when [quoted text clipped - 5 lines] > >In short, it's a report of a statistical anomaly, NOT a clinical result. Well Steve, yes. I agree. You agree. The new study was setting out to show exactly the anomalies of observational-only studies. And I did not fail to include in my fuller excerpt not quoted by you: "Randomized clinical trials have shown that androgen deprivation can improve survival in these patients." >I do wish that Mike had included that information Well, you see, I did. >it would not frighten men who are on ADT with information that is >untrue, If the whole of my extract is read, i) it is true. And ii) do men researching ADT (as I have been doing - due to go on it anyday with T3b lymph node involvement, G9) really get "frightened" - even if they misunderstand something? Do they look at one piece of any information and get "frightened"? If so we will all be frightened every moment of every day. >I'll now repeat my previous rants: I know, it's a way of getting going in the morning. Beats coffee. >Never never never trust what some >reporter claims about these matters (or much of anything else, for that >matter, but that's for another day and forum). Always always always seek >out the primary source of information. I'll say Amen to that. Steve your rant is in a good cause. But so should the more be used with care. I really don't believe it was in this case. And here's my little rant. Never, never, should we seek out an argument where there is scant justification for it. And in a way which could actually frighten - those who wish to contribute to this NG but may wonder what they are inviting upon themselves. Steve, I shall keep my tin hat on and continue trying to help members of this NG when I find information I believe will be of interest. As I know you always do. My very kind regards. Best wishes to everyone. MikeHi On April 27, Mike replied to me: > I am poking my head out of my air-raid shelter where deep instincts > from long-ago direct me to proceed with all due haste when stuff [quoted text clipped - 4 lines] > friendly fire. And that is said with the utmost respect to one of the > posters I much rely on to inform my current fight. (snip) Well, it's possible that I pulled the trigger prematurely. But when the post ends with "When the investigators analyzed data from the SEER registry of more than 5,000 men, they found that men treated with androgen deprivation actually had a higher risk of death from prostate cancer than men who did not receive the therapy," it is all too easy for men to be frightened. I still insist upon reference to the primary sources, especially when dealing with technical information. And in this case, I see no earthly purpose to be served by publishing it, except perhaps that the authors must, as they say in academe, "publish or perish." Perhaps publication in a journal devoted to statistical matters would have been more appropriate. We're all laymen here, trying as best we can to learn and to cope. To rely upon interpretations of medical information written by journalists, who are for the most part even more ignorant than we are, is asking for trouble, IMO. Regards, Steve J >Well, it's possible that I pulled the trigger prematurely. > [quoted text clipped - 3 lines] >had a higher risk of death from prostate cancer than men who did not >receive the therapy," it is all too easy for men to be frightened. Oh dear, Steve, no, it wasn't my post which ended like that, it was the original report. And your quote wasn't the whole of how 'it', or my post ended. You omitted my, and the report's, para. (again):" "Randomized clinical trials have shown that androgen deprivation can improve survival in these patients." I wouldn't expect a single person here to evaluate the whole report on my couple of paras. - which were however an accurate representation of every word. >I still insist upon reference to the primary sources, especially when >dealing with technical information. And in this case, I see no earthly [quoted text clipped - 7 lines] >who are for the most part even more ignorant than we are, is asking for >trouble, IMO. I say again, Amen to that. But as layman we can't always find an academic source of interest; but we can find reputable journals. That must be allowed. Then, we do our own follow-ups. And so, as the sun sets on this side of the pond, I stow my keyboard, and well-worn fingers, and bid a fond farewell and Alloha to all our highly valued contributors. Kind regards, Steve And my best wishes to all. MikeHi On April 27, Mike wrote: Quoting me >> Well, it's possible that I pulled the trigger prematurely. >> [quoted text clipped - 3 lines] >> had a higher risk of death from prostate cancer than men who did not >> receive the therapy," it is all too easy for men to be frightened. He replied > Oh dear, Steve, no, it wasn't my post which ended like that, it was > the original report. Mike must be a barrister ;-) It is indeed the last sentence in Mike's post. I did not accuse Mike of authorship. > And your quote wasn't the whole of how 'it', or > my post ended. You omitted my, and the report's, para. (again):" > "Randomized clinical trials have shown that androgen deprivation can > improve survival in these patients." My *point* is that Mike's post, especially ending as it did, could be misleading, causing folks to suppose that ADT increases a patient's risk of death from PCa. (snip) >> I still insist upon reference to the primary sources, especially when >> dealing with technical information. And in this case, I see no earthly [quoted text clipped - 11 lines] > academic source of interest; but we can find reputable journals. That > must be allowed. Then, we do our own follow-ups. For the most part, these articles, mostly by journalists, not scientists, will include sufficient information for one to track down the primary source. But I reckon that only obsessives like me would go to the trouble and thus avoid being misled. Good night, Mike. Regards, Steve J "Facts are stubborn things; and whatever may be our wishes, our inclination, or the dictates of our passions, they cannot alter the state of facts and evidence." --John Adams Stuff I said and his replies: Sreve My typing fingers, one on each hand, are groaning about all the work you're putting me to. So - and also because I still love you - I ain't gonna dispute no more. So I'm only gonna have a word with your postcripted President, John Adams. .. Steve finished: >Good night, Mike. > [quoted text clipped - 6 lines] >state of facts and evidence." > --John Adams Hi Your Majesty Mr President I'm sure a person of your great eminence will still be looking down from above. So I humbly reply: John, my old mate, Sir, you had the good fortune in the 1780's etc never to know prostate cancer. If you had we are quite sure in your wisdom you would have added the caveat: .."However , in Pca research, whatever our wishes, our inclinations, or the dictates of our fashion, the facts and evidence may change every day." I remain, Sir, Your Most Honourable Servant. MikeHi On April 28, Mike wrote, in pertinent part: > My typing fingers, one on each hand, are groaning about all the work > you're putting me to. So - and also because I still love you - I ain't > gonna dispute no more. > So I'm only gonna have a word with your postcripted President, John > Adams. I think that, given due respect, debate is a good learning tool. > Steve finished: > [quoted text clipped - 19 lines] > whatever our wishes, our inclinations, or the dictates of our fashion, > the facts and evidence may change every day." Amen to that. In medical matters, not solely PCa, hardly anyone agrees with anyone. Regards, Steve J Here's another Yank president: "The price of freedom from cancer is eternal vigilance." --paraphrasing Thomas Jefferson |
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