Revolution in Screening for Prostate Cancer
Why a patient’s column?
This is not a doctor’s column. I am a patient of Dr. Catalona and a member of the URF Board. This column attempts to provide a patient’s perspective on prostate cancer to the readers of QUEST.
To review my prior columns on Dr. Catalona’s Website, www.drcatalona.com. Insert my name in the “QUEST Articles” search engine.
Dr. Catalona recommends lower PSA screening threshold
The July 24 issue of the New England Journal of Medicine contains a study by Dr. Catalona and his associates that completes his 8-year series of research publications on lowering the PSA screening threshold from 4.0ng/ml to 2.6ng/ml.
This study was widely reported in the newspapers. The typical headline focused on the limitation of current PSA screening practice, and said something like, “Screening test may miss 82 percent of tumors, study finds“.
A more helpful, but longer, headline would have added, “Lowering the screening threshold will double the chance for tumor detection and greatly reduce the chance for recurrence and death.”
In either headline scenario, patients can view this news as a revolution in their opportunity for successful treatment.
Following is a dialogue between an imaginary patient and me concerning this study:
Questioning Patient (QP): What does this study on PSA screening thresholds mean to me?
Jules: The suggested lower threshold of 2.6ng/ml is not only concerned with detecting more cancer. It is, more importantly, concerned with detecting cancer earlier. With earlier detection comes a lower rate of recurrence and death. Detecting and treating earlier is a powerful approach to getting lower recurrence and death rates.
(QP): Can you give me a brief summary of this study?
Jules: The study reports that if we stay with the current PSA threshold (the PSA boundary between YES there is danger and NO its safe) of 4.0ng/ml, then for men under 60 years of age, when cancer is truly present, the doctor will correctly advise us to proceed with a biopsy 18% of the time, while 82% of the time he will falsely tell us that there is no reason to proceed.
However, if the PSA threshold is lowered to 2.6ng/ml, then, when cancer is truly present, doctors will give us correct advice 36% of the time, and will tell us that there is no reason to proceed 64% of the time.
Amazingly, just in reducing the PSA threshold by this small amount (from 4.0 to 2.6ng/ml), we have doubled our chances of finding cancer early (18% to 36%), while the study shows that we added only 4% to our risk of getting unnecessary biopsies. Note: The results for men over age 60 are similar but less dramatic.
QP: I still dont understand how the earlier detection results in these benefits.
Jules: In Catalona 1999, he reported the probability of recurrence over 7 years for 1778 of his consecutive patients. His PSA graphs illustrate these benefits.
The study found 12% less chance of recurrence if Dr. Catalona performed surgery on a man with a PSA between 2.6 and 4.0ng/ml, than if he used the conventional range (that he established in 1991) of 4.0 to 10.0ng/ml.
If we use Dr. Catalona’s current experience rate of about 80% non-recurrence, then with the lower threshold for detection and treatment, the non-recurrence rate over 10-years should increase to between 90% and 95% depending on the severity of the case.
These results will have to be further clinically verified, but it’s a very important result since recurrence has been shown to set in motion a cycle of events leading to prostate cancer death unless some later therapy is hopefully possible.
The reason for the improvement in this low PSA range is that the tumor is small, the variability in results is low, and when surgery is performed, it’s very likely to be totally curative for the great majority of men regardless of any other characteristic of the tumor.
Here’s the key point: If the doctors stay with the current threshold of 4.0ng/ml, then we will continue to have significant rates of recurrence. If they reduce the threshold to 2.6ng/ml, then surgical treatment will, for the great majority of men, truly mean cure; and the high Gleason Score exceptions can be given more therapy at an early stage.
QP: The idea that I have to do something about a lower PSA reading scares me. Why can’t doctors leave well enough alone? If I’m treated for prostate cancer and it recurs, then I’ll take the additional treatment required at that time.
Jules: With the current state of medical knowledge, it’s very difficult to respond to recurrence.
For several years I have told everyone the amazing story of Dr. Judah Folkman’s invention of anti-angiogenisis. The idea is to cut off the blood supply to the tumor and manage the disease, not cure it.
Dr. Carter of Johns Hopkins recently did a literature search and found that 200 different trials have now been run on potential anti-angiogenisis drugs and nothing worked. I thought that it was impossible for everything to fail, but that’s what has happened so far.
I’ve also followed vaccine therapies. The idea is to boost our own immune system to fight the cancer. Again, some small progress has been made, but very little.
The standard treatment of salvage radiation after a surgical recurrence has also had mixed results for long-term (10-year) non-recurrence.
I endlessly chase after possible therapies for recurrence. There are a very large number of suggestions and trials. However, in every area the situation is confusing, and the suggested therapies are often extremely unpleasant, or worse, for the patient.
A friend of mine visited a medical oncologist of high repute who has, in the past, listed all kinds of treatments for recurrence. “What did he say about the alternatives?” I asked.
“The doctor just sat there quietly and shook his head “NO” as I read off each option,” my friend said.
My friend is trying the experimental use of high dose calcitriol (Vitamin D) with another famous oncologist. So far the result is not great but we’re all hoping.
A well-known and relatively gentler therapy offered for recurrence is intermittent hormonal therapy. One suggested protocol is to chemically suppress testosterone production from the testes and adrenal glands with drugs like Lupron, Zoladex, and Casodex, until the PSA drops to a low value, and then keep PSA low in the “Off cycle” by continuing to take Proscar (finasteride). Several years later (maybe even 5 years if the treatment is successful) when the PSA again rises to unacceptable levels, the man must endure another cycle of hormone therapy.
However, as Dr. Catalona reported in the last issue of Quest, the use of Proscar is now embroiled in a major medical controversy. Even when this protocol works well, over time, the therapy is likely to stop being effective.
I don’t mean to be too negative about treating recurrence of prostate cancer. Very large numbers of men are alive and well and are managing their recurrence problem, often in very innovative ways. However, at the very least it’s difficult to find a path to joy and harmony if the disease recurs.
QP: What choice would you personally make about use of a lower PSA screening threshold?
Jules: Medical advice is the responsibility of doctors. But for myself, and only for myself, if I could relive my life based on what is now known, I would have had screening and then treatment at the lower PSA threshold.
I would have been on Dr. Catalona’s surgical table as soon as I could after careful diagnosis of my case had shown that treatment was needed.
My personal view is that I would much rather take the small risks associated with surgery done by an expert than endure endless worry that mine will be one of the cases of recurrent cancer. But everyone must make his own choice in such serious matters.
QP: Any closing thoughts?
Jules: Dr. Catalona has caused another revolution in the strategy of screening and treatment. It would be wise for men to discuss the results of Dr. Catalona’s study with their doctors and come to their own conclusions.
You are encouraged to offer comments or ask questions about this column by contacting Dr. Catalona at his website: send me an e-mail at firstname.lastname@example.org
Click here to read the next article, Where We Stand In Trying To Be Cured, in the One Man to Another series from Jules Reichel.