Prostate image yielded as part of 3D staging biopsy with cancerous lesions in mud yellow, urethra in green. This is completed prior to focal cryotherapy treatment - where a cryo-probe at -90C is inserted into the perineum to freeze cancer cells. The procedure can last from an hour to an hour and forty five minutes. But no promises are made to rid the cancer entirely.
The recent press reports of lowered cancer survival rates, and a WSJ editorial on the subject, make it incumbent on critical- thinking citizens to examine such stats and whether they're really valid. We read in the WSJ piece from January 9, for example, that: "the cancer death rate in the U.S. fell 2.2. % from 2016 to 2017 "the largest single year drop ever recorded". This according to the latest report in the American Cancer Society. However, we also learn:
"The drop is largely driven by progress against lung cancer".
A result of great new terrific treatments? Actually not. More a case that such lung cancer deaths were largely fueled by "fewer people smoking."
Meanwhile we learn that (ibid.):
"Doctors made progress in breast, prostate and colorectal cancers."
But how much? According to a WSJ editorial ('Where You Want To Get Cancer', January 10, p. A16):
"The five year survival rate is now 98 % for prostate cancer, 92% for melanoma and 90 % for breast cancer"
But what does that even mean and is it 'more pie in the sky' or wishful thinking than anything else? A recent issue of Skeptic magazine (vol. 24, No. 4, 2019) provides some clues in an article entitled 'How Much Longer Will Cancer Screening Myths Survive?' The author, Felipe Noguiera, cites two problems with figuring survival rates associated with screenings:
1)The lead time bias. I.e. when statistical studies include already screened patients, and
2) A length of time bias which occurs when screening is done periodically and cancer- contrary to what most people think - is a heterogeneous disease with different progression rates.
A key problem in respect of (1) which I've discussed before in the case of prostate cancer (when I referred to radiation, and radical prostatectomy treatments) is that screening allows many cancers to now be detected in the asymptomatic phase. That was how my prostate cancer was detected using a needle biopsy back in July, 2012 e.g.
Notes on a Prostate Biopsy: Don’t Fear and Don’t H...
In my case I was told non-action (e.g. watchful waiting) was not an option so I had to choose either the surgery (RP) or radiation. Well, I ended up choosing high dose brachytherapy in September that year. But four years later the cancer (evidently diagnosed from MRI biopsy, fusion biopsy and 3D screening- staging biopsy results e.g.
3D Staging Prostate Biopsy Unlikely To Come Into...
Returned. Would I have still survived this long (e.g. nearly 6 1/2 years) without any treatments? (I had another, focal cryotherapy treatment in June, 2017) The jury is still out according to the Skeptic author. As he writes (p. 34):
"Imagine that a group of patients without screening is diagnosed due to symptoms at an age of 63 years, but they die from the cancer at 65. Now, consider that screening (e.g. biopsy) detects the tumor at age 59 and the patients still die at 65. Thus, without screening the 5 year survival rate was 0 % but with screening it is 100 %, even though screening did not make them live any longer. Both groups of patients died at the same time. This is called the lead time bias."
In terms of (2), the effect arises because screening is done periodically( in my case, in July, 2012, in June 2016, September, 2016 and January, 2017. As the author points out:
"Basically, aggressive and more lethal cancers tend not to be detected by screening because they grow fast and cause symptoms between screening rounds. Similarly, screening tends to detect slow, progressive cancers. As a result a group of patients whose cancers were detected by screening will live longer than those diagnosed clinically imply because screening selected a group of patients with a better prognosis."
In other words, the success wasn't on account of the screening per se, but because that screening selected for the slower growing cancer. As the author adds:
"That means that screening detects abnormalities that meet the pathological criteria of cancer, but would not have caused symptoms or death in the patient's lifetime. This is called overdiagnosis."
The problem of overdiagnosis is that at the time of diagnosis it is not possible to know which cases will progress and which will not. So almost everyone is treated leading to overtreatment. That leads to another complication, i.e. "to look only for cancer specific mortality could miss deaths caused by treatment."
He then cites (p. 36) Swedish trials of mammography to show the problem of bias associated with cancer-specific mortality in breast cancer. Thus:
"For every other woman screened every other year for 12 years - while one cancer death was avoided, the total number of deaths increased by six."
In other words, the increased radiation endured in mammography screenings led to other cancers not related to the one originally detected and which caused a death. The conclusion?
We should publicly acknowledge that we cannot be sure whether early detection lengthens, shortens or has no effect on how long people live."
This comports with what I wrote in my November 9, 2018 blog post on the changed recommendations for prostate cancer screening, for example, e.g.
"Most experts agree that people with a life expectancy of 10 years or less don't need routine screening for cancer. One problem is that overscreening can lead to overdiagnosis and overtreatment. For instance, a screening might find a slow-growing cancer that wouldn't cause any harm within a person's lifetime if left undetected, a situation that's common with prostate cancer. If that's the case, it's not worth the burden and anxiety caused by testing and the potential for more—possibly invasive—follow-up procedures.
Yet, according to published studies, too many older adults continue to undergo unnecessary cancer screenings despite age- and health-related recommendations from professional groups.
Three groups that have weighed in on prostate cancer screening are the National Comprehensive Cancer Network (NCCN), the United States Preventive Services Task Force (USPSTF), and the American Urological Association (AUA). Following are their current recommendations for when to stop:
I'd also posted this on the Team Inspire prostate cancer forum and was met with a lot of pushback, some downright vitriolic, i.e.
"What are you a politician running for office? An insurance company agent? I am sick of you guys coming in here and trying to tell us to try to control costs and not to get these tests! I don't care how much they cost, even if I'm 78 I am gonna get them! Maybe I want to live to 95!"
"I'm in no position to contradict medical science on this, but 70 seems a bit young. Yes, it leaves a "life expectancy" of 10 years (in 2018, living in the U.S., given today's technology), but healthy people with good genes and healthy lifestyles routinely live well into their 90s. My G4+5 was discovered when I was 59. What if it had been 12 years later? Answer: a horrible death from PCa, diagnosed only after I became symptomatic, and far too late to treat it."
So there's no doubt that because of the feel good propaganda pushed by the likes of the WSJ editors (and other corporate media) it will be a long time before people back off on the benefits of screening, and indeed adhere to the revised recommendations.
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