tarhoosier said...
The point about baby boomers driving the numbers is not relevant as the statistics are per 100,000 men. The total number of men, larger now than 20+ years ago, is thus moot.
You are right, it is all controlled for in the "per 100,000" unit. This also controls for a significantly larger population since 1975 and even 1992. However there was a huge spike in new cases in 1992 compared to 1975, nearly 2.5 times though "only" 1.25 times as many deaths. I figure the huge spike was simply all due to increased diagnosis with the ever expanding amount of routine PSA testing done.
Then newly diagnosed cases per 100,000 dropped steadily from 1992 simply because - it seems reasonable to me anyway- so many men had already been tested and diagnosed. But the cases dieing per 100,000 also drops steadily.
It is in the years going forward that we should be able to tell if any good has been done, although it is possible that great good has been done already. As the boomers continue to age, assuming we have finally overcome that huge 1992 spike effect of vastly increased testing and IF PSA remains in use as often as it has been, I would expect to see numbers diagnosed per 100,000 to stay steady or probably increase steadily. If deaths don't also rise or even drop further we will know we are onto something good. If not, then maybe it has all been for nothing, or worse.
But for now, as we look at these seemingly mysterious numbers, it seems we need to first figure out one thing before they can be of any use to us:
Are there actually only about
1/2 as many men contracting PC today as there were in 1992? During the same time that skin cancers, for one, have skyrocketed despite sunscreen use and other precautions and skin cancers are being seen at ever earlier ages? And while, overall cancer incidence has dropped only 6% in the last decade?
This is the UK, but scroll down about
1/3 page to the chart on incidence over time.
www.cancerresearchuk.org/cancer-info/cancerstats/types/prostate/incidence/uk-prostate-cancer-incidence-statisticsNotice the very steep increase from about
1991 to 2003. Huge increase from about
45 per 100000 to 105! Pretty much like the figures given here, and all right in the middle of the NEW PSA testing era. Then from 2003 onward, almost no further increase in incidence. But steady. No drop. So this graph shows no decrease in the numbers of men per 100000 having PC, just no further steep increase due to increased testing. Remember, a lot of us, before PSA, would die of something else before we ever even knew we had PC. Especially in 1975. So there was not likely a 3+ times increase in the number of men getting PC from 1975 through 2003, there were just a whole bunch of men getting diagnosed in a relatively short period of time. Many who had PC for years and did not know it. And many who, even in 1985, would have died of something else with no one ever knowing they had PC, hence much lower INCIDENCE of PC ( as far as they knew then). But starting with PSA, we now knew these men had PC way before they died of MI, thus the apparent- but false- huge increase in incidence. Only a huge spike in diagnosis before death, not incidence.
"This may be due to diagnosis of early prostate cancers in younger men through PSA testing, leaving increasingly fewer cases which have not yet been diagnosed by the time men reach their 70s and 80s."
In the same way, I don't think there has been any decrease in incidence here either in the last decade or two, only a big decrease in diagnosis of new cases. The incidence in the UK, as shown in this chart, remains about
the same. Maybe even up a little in 2009 in the UK. But in the meantime, the death rate has dropped steadily since 1991, just like in the US. Though not near as much as in the US, maybe only by 1/4 instead of 1/2. But guess what? They don't do near as much PSA testing as we do. Not as much PSA testing AND death rates have not dropped as much. Scroll down for chart on lower death rates despite steady to slight increase in incidence:
www.cancerresearchuk.org/cancer-info/cancerstats/types/prostate/mortality/Here is yet another view:
www.drcatalona.com/quest/quest_spring09_3.htm""Since 1992 (the year after publication of my paper showing that PSA could be used as a first-line screening test for prostate cancer), rates of death from prostate cancer have fallen 37% in the US, more than for any other cancer in men or women," he said.
Dr Catalona noted that while the prostate cancer deaths are down significantly, there is now a decrease in screening which has resulted in a decreased incidence rate of prostate cancer.
"I think the reason for this finding of decreased incidence is that there is less PSA screening due in part to recent anti-screening propaganda. 52% of men 50 or older reported having a PSA test in 2004, down from 58 percent in 2001," he said.
He finds this decrease in prostate cancer screening alarming because he sees the decrease in deaths from prostate cancer clearly connected to early detection from PSA and DRE screening. More incidence, more early detection, could mean more lowering of death rates from prostate cancer...............
(death rates)The NCI reported the following data on prostate cancer death rates by years:
1975 -1987, an annual increase of 0.9%
1987-1991, an annual increase of 3.0%
In 1991, Dr. Catalona first reported in the New England Journal of Medicine that the PSA test could be used as a first-line screening test for prostate cancer.
1991-1994, an annual decrease of 0.6%
In 1994, Dr. Catalona reported on the pivotal multi-institutional study that led to the approval of PSA as an aid to the early detection of prostate cancer with a 4 ng/ml threshold recommendation for prostate biopsy.
1994-2005, an annual decrease of 4.1%"
I highly suspect that here, as in the UK, incidence is about
the same as 10 or 20 years ago, but death rates are dramatically lower. If incidence has indeed dropped by 1/2, we need to get with and figure out why so we can start doing whatever it is!
Post Edited (BillyBob@388) : 9/13/2014 11:41:03 AM (GMT-6)