Saturday, June 27, 2009
Blog Updates for June 2009
June 16/09.
Added to Free Monthly Prostate Cancer Magazines and Journals these lists of free medical journals (not necessarily in the field of urology):
NHS (UK)
http://www.library.nhs.uk/Default.aspx
NIH - Pubmed Central (US)
http://www.pubmedcentral.nih.gov/fprender.fcgi
Biomed Central
http://www.biomedcentral.com/browse/journals
June 16/09. On the Case Histories page we added: surgery takes effect immediately and also has the worst side effects immediately whereas radiation has relatively benign immediate side effects in the short term but over the following 24 months as the radiation kills the prostate cancer cells the side effects kick in [PMID: 19395191].
June 7/09. On the Calculators page we added:
Wolfram Alpha provides a box in which you enter a query and find out where among the population you stand on various medical tests, e.g. enter one of these:
psa 5 age 60
vitamin d 25 age 60 male
bmi 25 age 60 male
life expectancy age 60 male
blood pressure 125/75 age 60 male
ldl cholesterol 125 age 60 male
hdl cholesterol 50 age 60 male
or if you omit the test value then it gives the population reference range, e.g. enter:
psa age 60
Saturday, May 30, 2009
Blog Updates for May 2009
May 25/09. On the Calculators page we added: Castrate Resistant Prostate Cancer. This calculator answers the question of whether the patient has castrate resistant prostate cancer and what the optimal treatment is. In association with this calculator readers may wish to view this presentation by Nicholas Vogelzang (papers).
May 10/09. In Advice to the Newly Diagnosed we added: Major medical centers routinely circulate news releases on highly limited human studies (uncontrolled interventions, small samples [< 30], surrogate primary outcomes or unpublished data) yet in a study of 40 such releases "58% lacked the relevant cautions". [PMID: 19414840] [Full Text]. Journalists then uncritically report on them.
May 8/09. In How Healthy Men Can Reduce Their Risk we added: In a 2005 review of the data from 50,000 men in the Health Professionals study, Harvard researchers found that those with the highest level of physical activity had only one third of the rate of advanced prostate cancer relative to those at the lowest level of physical activity (after adjusting for risk factors such as BMI, etc.). Also those at the highest physical activity level had only 26% the rate of fatal prostate cancer relative to those at the lowest level. The benefit only applied to those at the highest level of physical activity. Also the overall overall prostate cancer rates were not reduced but it did reduce advanced and fatal rates. See [PMID: 15883238] [Full Text].
May 7/09. In Testosterone Metabolism and Prostate Cancer we added: A May 2009 study [PMID: 19414838] found "a significant statistical association between patients' eventual death from prostate cancer and abnormal expression (using protein staining) of "bcl-2", which regulates cell death, or of the "p53" tumor suppressor gene. Similarly, high microvessel density (the number of small blood vessels in the tumor) from biopsy specimens taken at diagnosis was also associated with an increased risk of death over 11 to 16 years." [summary].
May 6/09. In Bradford Hill Criteria of Causation we added: A 2007 paper in PLoS Medicine estimated that 40% of all medical papers published were shaped behind the scenes by pharmaceutical companies in a process the paper refers to the ghost management (which is not the same as ghost writing). See [PMID: 17896859] [Full Text].
May 4/09. In Lymph Node Dissection added: A 2009 review of Lymph Node Dissection in European Urology is available in [PMID: 19297079] [Full Text]. Note the tables in particular in this last review.
May 1/09. In Advice to the Newly Diagnosed we added: This Yananow article Elephant in the Room by Terry Herbert has further statistics and information on outlook.
May 1/09. In PSA Screening and Early Detection. Part 3. Current Environment we added: Since the above was written the AUA Best Practices Statement has been released. A [summary] is available as well.
Friday, April 24, 2009
Blog Updates for April 2009
Apr 23/09/. In ED After Prostatectomy. Part 2 - Rehabilitation we add a reference to this Feb. 2009 paper in the Canadian Urological Association Journal: [PMID: 19293974] [Full Text] which reviews rehabilitation.
Apr 23/09. In Choosing a Surgeon - Part I. Considerations, Choosing a Surgeon - Part I. Considerations we added: Different primary care physicians have different approaches toward PSA testing [PMID: 19296843 ].
Apr 20/09. On the Calculators page under SWOP the link has changed and risk indicators 3-6 are no longer present.
Apr 24/09. In RP vs. LRP vs. RLRP - Part 4. What Surgeons and Others Say: Maurice Anidjar (papers) provides the following table (slightly abbreviated here) in Our Voice vol. 14 No. 1 pg. 10 (2009):
Apr 24/09. In Radiation risks associated with Prostate Cancer we added: A study presented at the April 2009 American Roentgen Ray Society meeting based on 100 physician surveys in various specialities found that 63% underestimated radiation exposure from abdominal-pelvic CT scans and only 20% thought that radiation risk was a part of disclosure. See this PSA Rising article.
Apr 23/09. In Choosing a Surgeon - Part I. Considerations, Choosing a Surgeon - Part I. Considerations we added: Different primary care physicians have different approaches toward PSA testing [PMID: 19296843 ].
Apr 20/09. On the Calculators page under SWOP the link has changed and risk indicators 3-6 are no longer present.Apr 24/09. In RP vs. LRP vs. RLRP - Part 4. What Surgeons and Others Say: Maurice Anidjar (papers) provides the following table (slightly abbreviated here) in Our Voice vol. 14 No. 1 pg. 10 (2009):
| Open | Laparascopic | Robotic | |
| Incision | Mideline abdominal opening from pubic bone to navel | 4-5 tiny incisions in the lower abdomen | 5-6 small lower abdominal incisions |
| Blood Loss | About 700 ml | Average 400 ml | 150 ml |
| Duration of procedure | 2.5 hours | 2 hours | 2 hours |
| Recovery | bladder catheter in place for at least 2 weeks; in-hospital recovery usually 4 days; convalescence up to 6 weeks | Catheter removed after 4-7 days; less pain; shorter hospital stay (2 days) and convalescence (4 weeks) | Catheter usually removed after 7 days; shortest hospital stay (1 day) |
| Continence | As high as 90% at 1 year | Long-term results at least equivalent to those reported with open surgery | Recovery of urinary control appears to be earlier than with open surgery |
| Potency | Depending on nerve-sparing, can be up to 85%; takes 18 months or longer | Long-term results at least equivalent to those reported with open surgery | Results at least equivalent to best results from open and laparascopic approaches |
| Surgeon skills involved | Measured by ability to eliminate the entire tumor and preserve patient's continence and potency | Major learning curve reuired for surgeon to master the technique | Shorter learning curve than with laparascopic surgery |
Apr 24/09. In Radiation risks associated with Prostate Cancer we added: A study presented at the April 2009 American Roentgen Ray Society meeting based on 100 physician surveys in various specialities found that 63% underestimated radiation exposure from abdominal-pelvic CT scans and only 20% thought that radiation risk was a part of disclosure. See this PSA Rising article.
Friday, March 27, 2009
Blog Updates for March 2009
Mar 27/09. In Screening and Early Protection. Part 3 - Current Environment we added: In response to two studies on PSA testing the president of the AUA stated: "The American Urological Association has read with great interest the coverage surrounding the two studies about prostate-specific antigen (PSA) testing recently published in the New England Journal of Medicine, and is concerned about the alarm these two studies have raised with patients. The decision to screen for prostate cancer is a personal one that a man should make in conjunction with his physician or urologist. Because most cancers need to be caught in their earliest stages to achieve the best outcome for the patient, disparaging the PSA test puts men - particularly with certain risk profiles - at risk for life-threatening disease. Prior to the use of the PSA test, tumors were found mostly in advanced - and less treatable - stages, giving patients far fewer options for treatment. These studies, as well as the 2008 United States Preventive Services Task Force recommendation that men stop PSA testing after the age of 75, have potential for harm if they are not explained clearly to patients or reviewed in the context of the full debate on PSA. It is the opinion of the AUA that the PSA test is a valuable screening tool that saves lives - and men with concerns about elevated PSA scores should consult their urologists about next steps.
These two studies do not clearly assert that PSA testing causes more harm than benefit. In one of the two studies, 52 percent of men in the "non-screened" arm had recent PSA tests, thus enriching the non-screened arm with men who had normal PSA levels and reducing the chance for prostate cancer death in this arm of the study. This means that more than half of the men in the non-screening arm of the study were screened, making it difficult to demonstrate a difference. In the other study, there was actually a 20 percent reduction in death from prostate cancer with a relatively short follow-up of only nine years. This is an important point. The benefit of screening may not be demonstrable until significantly longer follow up is reached for both trials. These studies therefore do not lead to the conclusion that PSA screening should be abandoned.
Men who are concerned about these studies should talk with their urologists about their particular risk profile and whether regular PSA testing is best for them.
The AUA is presently finalizing a new Best Practice Statement about prostate-specific antigen testing that will be unveiled during our upcoming Annual Meeting. These studies are being addressed in more detail in the Statement, but do not change the AUA's position that PSA is a valuable screening tool and should be appropriately offered to men. This document will be made available to the public in April." [link].
Also: The following statement was issued by the AUA Foundation on March 19, 2009 and is attributable to AUA Foundation Executive Director Sandra Vassos, MPA:
The American Urological Association Foundation (AUA Foundation) is concerned that two major studies about prostate-specific antigen (PSA) testing may present conflicting information to patients about the value of this critical prostate-cancer screening test. The benefits of regular screening and early detection should not be discounted in the overall population. The decision to screen for prostate cancer with PSA and digital rectal examination should incorporate other known risk factors, including family history of prostate cancer, age, ethnicity/race, and whether or not the individual has had a previous negative prostate biopsy.
Men should understand that studies such as these are just a part of the overall national discussion about PSA testing. An overwhelming body of evidence exists that supports the value of this test and that screening has the potential to save lives. The AUA Foundation strongly believes that the decision to screen is one that a man should make in conjunction with his physician and supports the screening recommendations of the American Urological Association. The Association is expected to release a new best practice statement about PSA testing during the group's upcoming Annual Scientific Meeting in Chicago next month. [link]
March 13/09. In ED After Prostatectomy. Part 2 - Rehabilitation we add: John Mulhall has recently written a patient-oriented book.
These two studies do not clearly assert that PSA testing causes more harm than benefit. In one of the two studies, 52 percent of men in the "non-screened" arm had recent PSA tests, thus enriching the non-screened arm with men who had normal PSA levels and reducing the chance for prostate cancer death in this arm of the study. This means that more than half of the men in the non-screening arm of the study were screened, making it difficult to demonstrate a difference. In the other study, there was actually a 20 percent reduction in death from prostate cancer with a relatively short follow-up of only nine years. This is an important point. The benefit of screening may not be demonstrable until significantly longer follow up is reached for both trials. These studies therefore do not lead to the conclusion that PSA screening should be abandoned.
Men who are concerned about these studies should talk with their urologists about their particular risk profile and whether regular PSA testing is best for them.
The AUA is presently finalizing a new Best Practice Statement about prostate-specific antigen testing that will be unveiled during our upcoming Annual Meeting. These studies are being addressed in more detail in the Statement, but do not change the AUA's position that PSA is a valuable screening tool and should be appropriately offered to men. This document will be made available to the public in April." [link].
Also: The following statement was issued by the AUA Foundation on March 19, 2009 and is attributable to AUA Foundation Executive Director Sandra Vassos, MPA:
The American Urological Association Foundation (AUA Foundation) is concerned that two major studies about prostate-specific antigen (PSA) testing may present conflicting information to patients about the value of this critical prostate-cancer screening test. The benefits of regular screening and early detection should not be discounted in the overall population. The decision to screen for prostate cancer with PSA and digital rectal examination should incorporate other known risk factors, including family history of prostate cancer, age, ethnicity/race, and whether or not the individual has had a previous negative prostate biopsy.
Men should understand that studies such as these are just a part of the overall national discussion about PSA testing. An overwhelming body of evidence exists that supports the value of this test and that screening has the potential to save lives. The AUA Foundation strongly believes that the decision to screen is one that a man should make in conjunction with his physician and supports the screening recommendations of the American Urological Association. The Association is expected to release a new best practice statement about PSA testing during the group's upcoming Annual Scientific Meeting in Chicago next month. [link]
March 13/09. In ED After Prostatectomy. Part 2 - Rehabilitation we add: John Mulhall has recently written a patient-oriented book.
Saturday, February 28, 2009
Blog Updates for Februrary 2009
Feb 28. In How Healthy Men Can Reduce Their Risk we added: AR5 Inhibitors. ASCO and AUA issued the following guidelines on AR5 inhibitors in February 2009:
Feb 27. In Post RP Urinary Incontinence Progression we added: Contradicting prevailing wisdom is a Feb 2009 study of 731 men which found that even after 24 months post-prostatectomy that 20% of men showed marked improvement in erectile dysfunction and continence and an even greater percentage showed improvement though not marked. [PMID: 19091349].
Feb 27. In Lymph Node Dissection added: An October 2008 review of Lymph Node Dissection is available in [PMID: 19044297] [Full Text].
Feb 1. Added the following blog to the Blogs: line in the right margin: Tewari.
- Men who have a PSA with a score of 3.0 or below who already get yearly PSA tests, or expect to get a yearly PSA test, and show no signs of prostate cancer may benefit from talking with their doctor about the risks and benefits of a 5-ARI, such as finasteride, for the prevention of prostate cancer. The advantages are a lower risk of prostate cancer and improvement in urinary problems (if present), and the reduction of future urinary problems. The potential risks include the possibility of developing high-grade prostate cancer and/or a chance of short-term (one to two years) sexual problems.
- Men who are already taking a 5-ARI to treat urinary problems may also benefit from talking with their doctors about using this drug for the prevention of prostate cancer, understanding that the improvement in urinary symptoms should be weighed against the potential risks of developing high-grade prostate cancer.
Feb 27. In Post RP Urinary Incontinence Progression we added: Contradicting prevailing wisdom is a Feb 2009 study of 731 men which found that even after 24 months post-prostatectomy that 20% of men showed marked improvement in erectile dysfunction and continence and an even greater percentage showed improvement though not marked. [PMID: 19091349].
Feb 27. In Lymph Node Dissection added: An October 2008 review of Lymph Node Dissection is available in [PMID: 19044297] [Full Text].
Feb 1. Added the following blog to the Blogs: line in the right margin: Tewari.
Saturday, January 31, 2009
Blog Updates for January 2009
Jan 31. In Advice to the Newly Diagnosed we added: Also see this January 2009 study [PMID: 19054189] and Medical New Today summary which found that for patients with Gleason Score 7 or less (59.1% of the patients) that survival was not substantially worse than men without prostate cancer.
Jan 19. In the Historical Developments Dr. Donald Gleason, developer of the Gleason Score, dies Dec 28th. See LA Times
Jan 19. In PSA Screening and Early Detection. Part 3. Current Environment we added: "The American Cancer Society recommends that health care providers discuss the potential benefits and limitations of prostate cancer early detection testing with men and offer the PSA blood test and the digital rectal examination annually, beginning at age 50, to men who are at average risk of prostate cancer and who have a life expectancy of at least 10 years. Those men who indicate a preference for testing following this discussion should be tested. Men at high risk of developing prostate cancer (African Americans or men with a close relative diagnosed with prostate cancer before age 65) should have this discussion with their provider beginning at age 45. Men at even higher risk (because they have several close relatives diagnosed with prostate cancer at an early age) should have this discussion with their provider at age 40." ACS 2009
Jan 11. In Advice to the Newly Diagnosed we added: Unfortunately even papers in leading medical journals can be misleading. The abstract of a paper [PMID: 18801517] in the Journal of Urology (one of the top urology journals) indicated that the relative risk of developing bladder cancer among those with external radiation for prostate cancer was 1.42 times that of the rest of the population, i.e. 42% higher; however, the risk of bladder cancer in the population is low so the absolute risk may only be a few percentage points. By only citing relative risks a very misleading impression is given even though the data presented may be accurate. See Radiation risks associated with Prostate Cancer for a better presentation. In PC Infolink the writer point out that the authors of the study were from a urology department (where surgery, not radiation, would be done) and wonders: "if a similar study carried out by members of a department of radiation oncology might have reached a different conclusion that emphasized the occurrence of erectile dysfunction and incontinence! Caveat emptor."
Jan 5. In Testosterone Metabolism and Prostate Cancer we added: Summarizing the situation, Judy Foreman writes in the January 5, 2009 Boston Globe that: "In 2006, Morgentaler cowrote a study on 345 men with low testosterone. The study - published in the journal Urology and not industry funded - showed prostate cancer risk was higher in men with the lowest testosterone, a finding supported by a handful of other small-scale studies using human subjects. That was contrary to findings suggested by the Physicians' Health Study in 1996, a discrepancy doctors can not fully explain." On the other hand, another view expressed in the same article was: "To say that testosterone replacement therapy is safe because we have no evidence it's harmful is making an assertion on faith, not facts," said Dr. Ian Thompson, chairman of the department of urology at the University of Texas Health Science Center at San Antonio, echoing the view of other doctors who disagree with Morgentaler." Morgentaler has written a book "Testosterone for Life".
Jan 2. In Advice to the Newly Diagnosed we added: In particular, the absence of randomized trials should not be confused or equated with the absence of evidence (something that presentations which attempt to "simplify" the situation often do). As the authors of one critique write:
We are saying that a systematic review purporting to give an "evidence-based review" of the cardiovascular effects of n-3 fatty acids should not conflate an absence of well-controlled trials examining cardiovascular effects of ALA with an absence of evidence that ALA has any benefits for the cardiovascular system.[link]
Jan 2. In Can Most Studies be Wrong we add: Publication bias can be detected in meta analyses using funnel plots. See [link].
Jan 2. In Advice to the Newly Diagnosed we added: The FDA attempts to regulate health care advertising but its a very difficult task.
Jan 2. In Bradford Hill Criteria of Causation we added this reference to personalized medicine: [NY Times, Dec 29/08]
Sunday, December 28, 2008
Blog Updates for December 2008
To wrap up 2008 there were over 40,000 page views of this blog this year. The 10 most visited pages on this blog (most visted first, second most visited second, etc.) were:
The Palpable Prostate
The Palpable Prostate: Prostate Cancer Calculators
The Palpable Prostate: Biochemical PSA Recurrence
The Palpable Prostate: ED After Prostatectomy - Part 1. Introduction
The Palpable Prostate: Yananow Place Name Table
The Palpable Prostate: PSA Doubling Time (PSADT) - Part 2. Calculating PSADT with Graphics
The Palpable Prostate: ED After Prostatectomy - Part 2. Rehabilitation
The Palpable Prostate: Urinary Incontinence
The Palpable Prostate: PSA Doubling Time (PSADT) - Part 1. Introduction & Use
The Palpable Prostate: Bradford Hill Criteria of Causation
The blog updates during December 2008 were:
Dec 23. On the Case Histories page we added: This case history appeared in the December 11, 2008 New England Journal of Medicine together with comments by three experts: [link].
Dec 23. On the Calculators page added: C. SWOP. A third site with an array of calculators including some not available at the above two is the http://prostate-riskindicator.com site, also referred to as SWOP, of The Prostate Cancer Research Foundation is closely related to the Department of Urology of the Erasmus MC, University and Medical Centre of Rotterdam.
December 21. In How Long Can Prostate Cancer Treatment be Delayed After Treatment we added: A recent NCI trial comparing immediate to delayed continuous hormone therapy concluded that there was no detectable difference between the two. See [PMID: 18823693] [NCI Trial Info] [NCI summary]. On the last link see the paragraph that starts "Immediate hormone therapy ..." that refers to EORTC-30846. The last link also refers to trials of intermittent hormone therapy with on and off again periods. The link concludes that the existing trials have been too small to base reliable conclusions on but it may be that all continuous therapy is ultimately rejected as a treatment in favor of intermittent therapy. The problem has been hypothesized to be that continuous therapy might selectively kill the weaker cancer cells undesirably allowing the more aggressive ones to dominate.
Dec 20. In Bradford Hill Criteria of Causation we added: The cause of inconsistent studies can sometimes be traced to an unaccounted for and possibly unknown factor whose presence affects the efficacy of the treatment. For example, Javier A. Menendez at the Catalan Institute of Oncology in Girona, Spain, and colleagues found that extra virgin olive oil was effective against breast cancer cells in HER2 positive individuals but not in HER2 negatives. At the time of the trials it was likely not known what the HER2 status of the subjects was but with this information new trials could be designed that stratified on HER2 analysing HER2 positive and negative subjects separately focusing on the subgroup, HER2 positives, where the effect is expected without dilution from the HER2 negative where no effect is expected. See [WebMD article] [PMID: 19094209].
Dec 20. On the Daily News line near the top of every page we added: Medical News Today
Dec 19. In Bradford Hill Criteria of Causation we added: The book Statistical Evidence in Clinical Trials by Stephen Simon suggests two other criteria that might be added to those of Bradford Hill: assessment of the possibility of fraud and of conflicts of interest. Regarding the latter see [PMID: 11900164] [Full Text] for a discussion of how one journal's editors discovered that authors not only had conflicts but that control was being exercised by pharmaceutical companies over the wording of their journal article submissions. Even worse [PMID: 18792536] and [PMID: 18413874] discuss actual ghostwriting of papers by industry sponsors.
Dec 19. In Testosterone Metabolism and Prostate Cancer we added: "Green tea catechin (-)-epigallocatechin gallate (EGCG) is a natural AR5 inhibitor. Flavonoids that were potent inhibitors of the type 1 5alpha-reductase include myricetin, quercitin, baicalein, and fisetin. Biochanin A, daidzein, genistein, and kaempferol were much better inhibitors of the type 2 than the type 1 isozyme. Several other natural and synthetic polyphenolic compounds were more effective inhibitors of the type 1 than the type 2 isozyme, including alizarin, anthrarobin, gossypol, nordihydroguaiaretic acid, caffeic acid phenethyl ester, and octyl and dodecyl gallates." (quotes from [PMID: 11931850])
Dec 18. In the Urinary Incontinence post added: In the right margin of this article entitled Pelvic Power (taken from Our Voice, 2008, 4(4)) physiotherapist Bill Landry describes 3 pelvic floor exercises and recommends performing them daily for 6 months after the catheter is removed and once or twice a week for the rest of your life after that. They should be performed "in postures/positions where leakage occurs" in order to get maximum benefit.
Dec 18. Pathology. A rule of thumb is that for each cubic centimeter (cc) of benign prostate tissue that 0.067 ng/ml of PSA will be produced. Thus for a prostate of 40cc (this is the volume of the prostate, not the volume of the tumor) one would expect a PSA of 40 x 0.067 = 2.68 ng/ml so if the actual PSA were 4.0 ng/ml then there is 4.0 - 2.68 = 1.32 ng/ml that is unexplained and might be due to cancer cells or other factor listed here. [link]. In a December 2008 paper Kato et al devised the following formulas for tumor volume (cc) and percent tumor volume as a function of PSA (ng/ml):[PMID: 19060997] [Full Text]
Dec 18. In Testosterone Metabolism and Prostate Cancer we added this [Friedman comment].
Dec 15. In Bradford Hill Criteria of Causation we added the following example of temporality: One patient remarked that those with more aggressive prostate cancer seemed weak but were they weak before they had it or did the cancer or treatment make them weak (reverse causality)? Which one came first would be essential to know.
Dec 15. In Advice to the Newly Diagnosed we added in reference to treatment decisions: Dr. Cary Presant makes similar remarks.
Dec 15. In Advice to the Newly Diagnosed we added: however, the situation is not actually so clear cut and as discussed in [PMID: 15717036] [Full Text] the value of randomized controlled trials may be over rated.
Dec 14. In Advice to the Newly Diagnosed we added: The book Statistical Evidence in Medical Trials by Stephen Simon has excellent non-technical coverage of how to understand medical research. It is intended for doctors to help them assess which advances to incorporate into their practice but its very easy to read by anyone. Simon's articles in the Journal of Andrology provide a portion of the material.
Dec 12. On the Daily News line near the top of every page we added: ScienceDaily
Dec 8. In Links section in the right margin we added this link to the November 2008 AUA Best Practices on Cryo statement: [AUA Cryo]. Also added this in the Treatments: line under (AUA) after [Cryo].
Dec 7. Removed one blog in the Blogs line under Links to the right whose volume of postings seems to have dropped off.
Dec 2. In Links section in the right margin on the Treatments line we added this link to a news article about 2008 report of UK agency NCEPOD, (NCEPOD), entitled Systemic Anti-Cancer Therapy: For better, for worse? which investigated deaths caused by chemotherapy : [link], (NCEPOD). The news article has a link to the NCEPOD site where the complete report and various summaries can be found.
Dec 2. In Choosing a Surgeon - Part I. Considerations, Choosing a Surgeon - Part I. Considerations we added: In December 2008 Andonian et al., at the 26th World Congress of Endourology (WCE) in Shanghai presented evidence of measurable changes in brain function among more experienced surgeons. See [link].
The Palpable Prostate
The Palpable Prostate: Prostate Cancer Calculators
The Palpable Prostate: Biochemical PSA Recurrence
The Palpable Prostate: ED After Prostatectomy - Part 1. Introduction
The Palpable Prostate: Yananow Place Name Table
The Palpable Prostate: PSA Doubling Time (PSADT) - Part 2. Calculating PSADT with Graphics
The Palpable Prostate: ED After Prostatectomy - Part 2. Rehabilitation
The Palpable Prostate: Urinary Incontinence
The Palpable Prostate: PSA Doubling Time (PSADT) - Part 1. Introduction & Use
The Palpable Prostate: Bradford Hill Criteria of Causation
The blog updates during December 2008 were:
Dec 23. On the Case Histories page we added: This case history appeared in the December 11, 2008 New England Journal of Medicine together with comments by three experts: [link].
Dec 23. On the Calculators page added: C. SWOP. A third site with an array of calculators including some not available at the above two is the http://prostate-riskindicator.com site, also referred to as SWOP, of The Prostate Cancer Research Foundation is closely related to the Department of Urology of the Erasmus MC, University and Medical Centre of Rotterdam.
- Risk indicator 1 is based on questions related to urinary frequency. It is assumed that no testing has yet been done.
- Risk indicator 2 is based on the result of a PSA test.
- The next three indicators are based on ultrasound results (0/1), digital rectal exam (0/1), prostate volume (ml) and PSA (ng/ml).
- Risk indicator 3 allows a more precise prediction of a positive biopsy than indicator 2 because it includes the results of the rectal examination, the ultrasonography (hypoechogenic lesions yes or no?), and of the volume of the prostate determined at ultrasonography. Each of these parameters has independent value in predicting biopsy outcome (Roobol et al, Prostate 2006).
- Risk indicator 4 is based on 10890 men who were previously screened, had a serum PSA < 4.0 ng/ml and were not biopsied. Of these men 1921 were biopsied 4 years later for PSA progression to = 3.0 ng/ml, 430 cancers were found (PPV 22.4%).
- Risk indicator 5 is based on 989 men who were previously screened, were biopsied and had no cancer. These men were again biopsied 4 years later with PSA values = 3.0 ng/ml, 120 cancers were found (PPV 12.1%). Both, a negative previous screen and, more importantly, a prior negative biopsy significantly decrease the risk of a later positive biopsy.
- Risk indicator 6 calculates the chance of having indolent prostate cancer which may not require immediate treatment. It uses Gleason Score, mm of cancer in biopsy, mm healthy tissue in biopsy, prostate volume (cc) and PSA (ng/ml).
December 21. In How Long Can Prostate Cancer Treatment be Delayed After Treatment we added: A recent NCI trial comparing immediate to delayed continuous hormone therapy concluded that there was no detectable difference between the two. See [PMID: 18823693] [NCI Trial Info] [NCI summary]. On the last link see the paragraph that starts "Immediate hormone therapy ..." that refers to EORTC-30846. The last link also refers to trials of intermittent hormone therapy with on and off again periods. The link concludes that the existing trials have been too small to base reliable conclusions on but it may be that all continuous therapy is ultimately rejected as a treatment in favor of intermittent therapy. The problem has been hypothesized to be that continuous therapy might selectively kill the weaker cancer cells undesirably allowing the more aggressive ones to dominate.
Dec 20. In Bradford Hill Criteria of Causation we added: The cause of inconsistent studies can sometimes be traced to an unaccounted for and possibly unknown factor whose presence affects the efficacy of the treatment. For example, Javier A. Menendez at the Catalan Institute of Oncology in Girona, Spain, and colleagues found that extra virgin olive oil was effective against breast cancer cells in HER2 positive individuals but not in HER2 negatives. At the time of the trials it was likely not known what the HER2 status of the subjects was but with this information new trials could be designed that stratified on HER2 analysing HER2 positive and negative subjects separately focusing on the subgroup, HER2 positives, where the effect is expected without dilution from the HER2 negative where no effect is expected. See [WebMD article] [PMID: 19094209].
Dec 20. On the Daily News line near the top of every page we added: Medical News Today
Dec 19. In Bradford Hill Criteria of Causation we added: The book Statistical Evidence in Clinical Trials by Stephen Simon suggests two other criteria that might be added to those of Bradford Hill: assessment of the possibility of fraud and of conflicts of interest. Regarding the latter see [PMID: 11900164] [Full Text] for a discussion of how one journal's editors discovered that authors not only had conflicts but that control was being exercised by pharmaceutical companies over the wording of their journal article submissions. Even worse [PMID: 18792536] and [PMID: 18413874] discuss actual ghostwriting of papers by industry sponsors.
Dec 19. In Testosterone Metabolism and Prostate Cancer we added: "Green tea catechin (-)-epigallocatechin gallate (EGCG) is a natural AR5 inhibitor. Flavonoids that were potent inhibitors of the type 1 5alpha-reductase include myricetin, quercitin, baicalein, and fisetin. Biochanin A, daidzein, genistein, and kaempferol were much better inhibitors of the type 2 than the type 1 isozyme. Several other natural and synthetic polyphenolic compounds were more effective inhibitors of the type 1 than the type 2 isozyme, including alizarin, anthrarobin, gossypol, nordihydroguaiaretic acid, caffeic acid phenethyl ester, and octyl and dodecyl gallates." (quotes from [PMID: 11931850])
Dec 18. In the Urinary Incontinence post added: In the right margin of this article entitled Pelvic Power (taken from Our Voice, 2008, 4(4)) physiotherapist Bill Landry describes 3 pelvic floor exercises and recommends performing them daily for 6 months after the catheter is removed and once or twice a week for the rest of your life after that. They should be performed "in postures/positions where leakage occurs" in order to get maximum benefit.
Dec 18. Pathology. A rule of thumb is that for each cubic centimeter (cc) of benign prostate tissue that 0.067 ng/ml of PSA will be produced. Thus for a prostate of 40cc (this is the volume of the prostate, not the volume of the tumor) one would expect a PSA of 40 x 0.067 = 2.68 ng/ml so if the actual PSA were 4.0 ng/ml then there is 4.0 - 2.68 = 1.32 ng/ml that is unexplained and might be due to cancer cells or other factor listed here. [link]. In a December 2008 paper Kato et al devised the following formulas for tumor volume (cc) and percent tumor volume as a function of PSA (ng/ml):
Tumor Volume (cc) = 3.476 + 0.302 x PSA
Tumor Volume (%) = 11.331 + 0.704 x PSA
Dec 18. In Testosterone Metabolism and Prostate Cancer we added this [Friedman comment].
Dec 15. In Bradford Hill Criteria of Causation we added the following example of temporality: One patient remarked that those with more aggressive prostate cancer seemed weak but were they weak before they had it or did the cancer or treatment make them weak (reverse causality)? Which one came first would be essential to know.
Dec 15. In Advice to the Newly Diagnosed we added in reference to treatment decisions: Dr. Cary Presant makes similar remarks.
Dec 15. In Advice to the Newly Diagnosed we added: however, the situation is not actually so clear cut and as discussed in [PMID: 15717036] [Full Text] the value of randomized controlled trials may be over rated.
Dec 14. In Advice to the Newly Diagnosed we added: The book Statistical Evidence in Medical Trials by Stephen Simon has excellent non-technical coverage of how to understand medical research. It is intended for doctors to help them assess which advances to incorporate into their practice but its very easy to read by anyone. Simon's articles in the Journal of Andrology provide a portion of the material.
Dec 12. On the Daily News line near the top of every page we added: ScienceDaily
Dec 8. In Links section in the right margin we added this link to the November 2008 AUA Best Practices on Cryo statement: [AUA Cryo]. Also added this in the Treatments: line under (AUA) after [Cryo].
Dec 7. Removed one blog in the Blogs line under Links to the right whose volume of postings seems to have dropped off.
Dec 2. In Links section in the right margin on the Treatments line we added this link to a news article about 2008 report of UK agency NCEPOD, (NCEPOD), entitled Systemic Anti-Cancer Therapy: For better, for worse? which investigated deaths caused by chemotherapy : [link], (NCEPOD). The news article has a link to the NCEPOD site where the complete report and various summaries can be found.
Dec 2. In Choosing a Surgeon - Part I. Considerations, Choosing a Surgeon - Part I. Considerations we added: In December 2008 Andonian et al., at the 26th World Congress of Endourology (WCE) in Shanghai presented evidence of measurable changes in brain function among more experienced surgeons. See [link].
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