Dan Franke, I agree that it makes things much more relaxed if we simply trust the experts, put ourselves in their hands and don't allow a worrisome thought to cross our minds. But then the question becomes, "Who are the experts? And what about when the experts are themselves divided about something?"
In this case, we have two sets of experts. The first are the practicing oncologists, whose life is seemingly dependent on routinely performing TRUS (transrectal-ultrasound guided) biopsies to diagnose and stage prostate cancer before proceeding to treat it. The second are the researchers, who carefully design and carry out studies intended to answer very important questions that have arisen over time about certain elements of what those practicing oncologists do. Dan Franke, you say, 'trust the experts'-- but what do you do when the second group of experts produces compelling evidence that there's a very serious-- and deadly-- problem with something the first group is doing?
I reread the article I read yesterday (which was essentially a summary called
"To Be Taken in Count: Prostatic Tumor Cells Break Free upon Needle Biopsy" and this evening (moments ago in fact) I read the study itself " Tumor-Associated Release of Prostatic Cells into the Blood after Transrectal Ultrasound-Guided Biopsy in Patients with Histologically Confirmed Prostate Cancer"-- both were in the January 2020 issue of Clinical Chemistry and both are available online if you copy and paste the titles into Google Search.
Here's the essence of the study: Medical science has only recently developed a method for detecting Circulating Tumor Cells (CTC) in the blood that is extremely accurate. (Circulating Tumor Cells are thought to be what seeds metastases.) This has allowed the researchers to establish which patients in the study (of those who turned out to have prostate cancer) had an increase in CTC after biopsy and how those patients fared as the years passed, compared with those patients who also had prostate cancer but who did NOT have an increase in CTC after biopsy. Before I tell you the result, let me remind everyone that although many men die of PC, that's because so many men have Prostate Cancer-- actually most PCs are indolent, and non-metastatic, and the men who have such tumors usually die of something else entirely.
Now, here are the results: Although all 115 men in the study were suspected of possibly having Prostate Cancer, only 75 men of the original 115 turned out to actually have it, based on the results of the biopsy that was taken. Of those 75, 1 was lost to follow-up. Of the remaining 74, 22 had an increase in Circulating Tumor Cells in their blood over their baseline level following the biopsy. 52 did not. So how did these 22 of 74 compare to the 52 of 74? Of the 22 men who had an increase in CTC in their blood following the biopsy, 10 showed progression of the prostate cancer during the time of follow-up (45%!!). Of the 52 men who did not have an increase in CTC in their blood following the biopsy, 8 of 52 showed Prostate Cancer progression during follow-up (only 15% compared to 45% in the first group). The result was both highly statistically significant and, even more importantly, highly clinically significant.
Dan Franke, you want to 'listen to the experts': surely you would acknowledge the men who conducted this study are experts. They say, and I quote, "The present results show that malignant epithelial cells can be released into the blood vessels during prostate biopsy in cancer patients, which might be associated with an increased risk of disease progression as indicated by follow-up analysis." I say, a little more bluntly-- although of course, I'm no expert-- that this is very scary news because it seems to mean that if your Prostate Cancer biopsy causes an increase in Circulating Tumor Cells in your blood (as happened with 22 of the 74 men--30%), then your risk of progressive disease is TRIPLED. And that means that it is highly likely that some of these 22 men (particularly some of the 10 in whom it already had progressed) will eventually die-- but not exactly of prostate cancer. Rather, they will die of what might very well be an indolent prostate cancer provoked into lethal behavior by the biopsy, the very thing used to diagnose it.
Dan, should someone like me-- a new possible case of PC-- simply ignore what the experts who conducted this study say? Or should we seek a way to get a diagnosis while avoiding the danger of turning a relatively lazy prostate cancer into a killer by virtue of a biopsy?