In interviews I did for the Prostate Cancer Foundation website, Weill Cornell Medicine urologist Jim C. Hu, MD, MPH (whose expert opinion was also featured in ours book)discusses what a rising or persistent PSA means after treatment for localized prostate cancer and what to do next. Remember the first lesson from Part 1: Don’t Panic!
How do you know if localized prostate cancer is curable? This answer to this question is clear for men undergoing radical prostatectomy: in the weeks after the operation, the PSA should be undetectable, falling to less than 0.1.
But for men undergoing radiation therapy, it’s more complicated: there is no definitive PSA cutoff to signal treatment success or failure. This is because radiotherapy – an external beam or seed of radiation (brachytherapy) – is designed to kill prostate cancerNo normal prostate tissue. It doesn’t kill the entire prostate – so PSA doesn’t go away completely.
Instead, the PSA falls, eventually reaching a level called a trough PSA nadir. Note: there may be a small bump along the way, called PSA “bounce”. This does not happen to everyone. it is more common in younger men. Bouncing PSA doesn’t mean you are not headed for a low, stable PSA. It’s just a weird thing which may be associated with inflammation of the prostate. it is temporary and usually occurs within the first two years after treatment. Then the PSA usually settles, remaining at a very low level.
It can take two to five years after radiation for PSA to bottom out. If it begins to rise again, no further testing is indicated until the PSA reaches a nadir of + 2 ng/ml. “The very term, ‘nadir +2,’ tells you that whole-gland radiation is not expected to kill all the cells inside the prostate,” says Jim Hu. “There are some benign cells that can still produce PSA. But if there are any remaining cancer cells, those cells will grow over time and eventually produce enough PSA to exceed this nadir + 2 threshold.” So if the cancer is still there after radiation therapy, it may take months or even years to find out about it.
If any cancer is still there, where is it?
There are many possibilities for where the cancer might be hiding, Hu says. “Cancer can be right inside the prostate. It could be inside and outside the prostate, but still in the immediate area.” Or, it may be further away—in a lymph node, perhaps. “The radiation may have killed the cancer inside the prostate, but there were some tiny metastases outside the prostate that were not touched by the radiation.”
The first place to look for recurrent cancer after radiation therapy is within the prostate – with an MRI and biopsy. What happens next? Let’s say the cancer is still in the prostate. “Typically, you can’t do more radiation to the prostate because that part of the body has already tolerated the maximum dose of radiation,” says Hu. “But in some centers, they’ll put some radioactive seeds (this is called brachytherapy) into the area where the cancer is or into the prostate.”
What about surgery? Many centers do not offer ‘salvage’ prostatectomy, ‘because a delay in diagnosing recurrence means the cancer may have spread. Some series of salvage radical prostatectomy [studies] showed that the chance of cure (with surgery after radiation) was only 20 to 30 percent.” Hu has performed 20 salvage robotic prostatectomies, but he makes sure his patients know Complications are much more likely when surgery is performed on an area that has undergone radiation therapy. This is because the tissue is already damaged to begin with. “The risk of incontinence, instead of being 1 to 2 percent, is now 50 to 80 percent for stress urinary incontinence (when urine leaks during certain activities, such as exercise) and there is a higher risk of rectal tissue – which becomes brittle after radiation – developing a hole or tear (called a fistula).
Other options: High-intensity focused ultrasound (HIFU) of the entire prostate is another option, as is cryotherapy (freezing the tissue inside the prostate). Both of these options, currently offered in some centers as focal therapy, have a lower risk of incontinence and ED than salvage prostatectomy, Hu explains—but he notes that here, too, PSA likely won’t become undetectable after the treatment. Instead, it’s back to waiting for PSA to reach its nadir. And if you have a PSMA PET scan or other imaging that shows the cancer has spread outside the prostate, such as to the bones, you and your doctor should discuss starting ADT, either alone or with a drug that targets androgen receptors, such as enzalutamide or abiraterone plus prednisone for combined perforation. These drugs reduce testosterone, cutting off the cancer’s “fuel supply,” and can be effective for many years.
In addition to book, I have written about this story and many more about prostate cancer on the Prostate Cancer Foundation website, pcf.org. The stories I have written are in the “Understanding Prostate Cancer” and “For Patients” categories. As Patrick Walsh and I have said for years in ours books, Knowledge is power: Saving your life can start with going to the doctor and knowing the right questions to ask. I hope all men put prostate cancer on their radar. Get a baseline PSA blood test in your early 40s and if you are of African descent or have a family history of cancer and/or prostate cancer, you should be screened regularly for the disease. Many doctors don’t do this, so it’s up to you to ask.
© Janet Farrar Worthington
