Statistical Facts of Life (and death)
Making Treatment Choices about Prostate Cancer requires understanding the difference between the mean (average) versus the median
The Lake Wobegon Effect
The Lake Wobegon Effect: Why Most Patients Are at Below-Average Risk The Lake Wobegon Effect | Annals of Internal Medicine
This commentary discusses the paradoxical finding that most patients are at below-average risk and can expect to experience less-than-average benefits from a treatment. This “Lake Wobegon effect,” the authors argue, can result in too many patients being screened, diagnosed, and treated.
Most patients are at below-average risk | Reuters
Typical approaches to prostate cancer screening, which assume that all men are at average risk, can lead to over-diagnosis as well as side effects such as impotence and incontinence from the tests to identify malignancies, Vickers and Kent note in their essay.
Testing for prostate-specific antigen (PSA), a protein produced in higher quantities by tumor cells, has only modestly reduced deaths from the disease but dramatically increased diagnosis and treatment, the authors point out.
Men who have the highest PSA levels at age 60 are about 20 times more likely to die from the disease than men with the lowest amounts of this protein, and almost all deaths by age 85 occur in this group of men with the biggest risk.
"The reason why over-detection of prostate cancer is a problem is that management of prostate cancer can have major side effects and complications, no matter what the treatment is," said Dr. Ian Thompson Jr., director of the Cancer Therapy and Research Center at the University of Texas Health Science Center in San Antonio.
Volume91_Issue4_Are_All_Cancer_Patients_above_Average.pdf
The Lake Wobegon effect: are all cancer patients above average? - PubMed - NCBI
Abstract
CONTEXT:
When elderly patients face a terminal illness such as lung cancer, most are unaware that what we term in this article "the Lake Wobegon effect" taints the treatment advice imparted to them by their oncologists. In framing treatment plans, cancer specialists tend to intimate that elderly patients are like the children living in Garrison Keillor's mythical Lake Wobegon: above average and thus likely to exceed expectations. In this article, we use the story of our mother's death from lung cancer to investigate the consequences of elderly people's inability to reconcile the grave reality of their illness with the overly optimistic predictions of their physicians.METHODS:
In this narrative analysis, we examine the routine treatment of elderly, terminally ill cancer patients through alternating lenses: the lens of a historian of medicine who also teaches ethics to medical students and the lens of an actuary who is able to assess physicians' claims for the outcome of medical treatments.FINDINGS:
We recognize that a desire to instill hope in patients shapes physicians' messages. We argue, however, that the automatic optimism conveyed to elderly, dying patients by cancer specialists prompts those patients to choose treatment that is ineffective and debilitating. Rather than primarily prolong life, treatments most notably diminish patients' quality of life, weaken the ability of patients and their families to prepare for their deaths, and contribute significantly to the unsustainable costs of the U.S. health care system.CONCLUSIONS:
The case described in this article suggests how physicians can better help elderly, terminally ill patients make medical decisions that are less damaging to them and less costly to the health care system.Get a C11 PET/CT Scan after Radical Prostatectomy PCa Recurrence?
Long-term survival of hormone-naive patients in biochemical failure post-surgery | THE "NEW" PROSTATE CANCER INFOLINKThis study was based on a retrospective analysis of data from 302 hormone-naive prostate cancer patients, all previously treated with radical prostatectomy, who were given a [11C]choline PET/CT scan between December 1, 2004 and July 31, 2007. Here are the key findings of the study:
- The average (median) PSA level of the 302 patients was 1.02 ng/ml.
- Average (median) patient follow-up after the PET/CT scan was 7.2 years (range, 1.4 to 18.9 years).
- 101/302 patients (33 percent) had a positive [11C]choline PET/CT scan.
- For patients who had a positive PET/CT scan,
- Average (median) prostate cancer-specific survival after prostatectomy was 14.9 years.
- The probability of prostate cancer-specific survival at 15 years post-surgery was 42.4 percent.
- For patients who had a negative PET/CT scan,
- Average (median) prostate cancer-specific survival after prostatectomy was not achieved during the follow-up period.
- The probability of prostate cancer-specific survival at 15 years post-surgery was 95.5 percent.
- On multivariate analysis,
- A positive [11C]choline PET/CT scan predicted prostate cancer-specific survival with a hazard ratio (HR) = 6.36.
- A Gleason score of > 7 predicted prostate cancer-specific survival with an HR = 3.11.
- An internally validated nomogram based on these data was able to predict prostate cancer-specific survival with an accuracy of 80 percent.
Genomic Testing gives more information
Prolaris_References_and_Links_Aprril_2015.pdfProlaris - A prognostic test for prostate cancer.
Prolaris®, a novel prognostic test developed by Myriad Genetic Laboratories, directly measures tumor cell growth characteristics for stratifying the risk of disease progression in prostate cancer patients. Prolaris is a risk stratification tool for patients with prostate cancer. It can enable you to better define a management strategy for your patients with prostate cancer, enhancing their quality of life without jeopardizing their life expectancy.
Test outperforms PSA, new Gold Standard
Studies find $1 test using gold nanoparticles outperforms PSA screen for prostate cancer Medical News Today
Two pilot studies conducted on blood serum samples collected at Florida Hospital and obtained from Prostate Cancer Biorespository Network (PCBN) revealed that the test has a 90–95% specificity and 50% sensitivity in detecting early stage prostate cancer, representing a significant improvement over the current PSA test.
Cancer biomarkers cling to gold nanoparticles, providing more accurate early-stage detection
A test that costs less than a $1 and yields results in minutes has been shown in newly published studies to be more sensitive and more exact than the current standard test for early-stage prostate cancer.
University of Central Florida scientist Qun "Treen" Huo holds the promise of earlier detection of one of the
deadliest cancers
among men. It would also reduce the number of unnecessary and invasive
biopsies stemming from the less precise PSA test that's now used.
The simple test developed by
"It's fantastic," said Dr. Inoel Rivera, a urologic oncologist at Florida Hospital Cancer Institute, which collaborated with Huo on the recent pilot studies. "It's a simple test. It's much better than the test we have right now, which is the PSA, and it's cost-effective."
After lung cancer, prostate cancer is the second-leading killer cancer among men, with more than 240,000 new diagnoses and 28,000 deaths every year. The most commonly used screening tool is the PSA, but it produces so many false-positive results - leading to painful biopsies and extreme treatments - that one of its discoverers recently called it "hardly more effective than a coin toss."
Pilot studies found Huo's technique is significantly more exact. The test determines with 90 to 95 percent confidence that the result is not false-positive. When it comes to false-negatives, there is 50 percent confidence - not ideal, but still significantly higher than the PSA's 20 percent - and Huo is working to improve that number.
The results of the pilot studies were published earlier this month in ACS Applied Materials & Interfaces. Huo is also scheduled to present her findings in June at the TechConnect World Innovation Summit & Expo in suburban Washington, D.C.
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