One of the holy grails of prostate cancer treatment is being able to treat the prostate cancer with as few or preferably no side effects. The side effects, currently, that patients’ worry about are bladder and sexual dysfunction.
One of the really interesting groups of treatment at the moment revolves around the notion of focal treatment of prostate cancer. In other words, just treating part of the prostate or half of the prostate, thereby preserving the other half and not giving the patient the sort of sexual and bladder dysfunction that you might get with treating all of the prostate.
The problem with that strategy really is two-fold. And these are concerning potential problems. The first is that we know from post-mortem studies that approximately 80 percent of prostate cancers are multi-focal. In other words, you tend to get more than one tumor within the prostate. So, it inherently doesn’t make much sense treating any part of the prostate when you have tumors studded throughout the prostate no matter what the biopsy shows.
The other principal concern about focal treatment of prostate cancer is that it is possible, and indeed common, to get multi-focal and polyclonal prostate cancer. In other words, you get lots of different grades of prostate cancer living throughout the prostate. It isn’t always the largest tumor that causes the problems. In other words, you can have a very small, highly aggressive prostate cancer that doesn’t show on biopsies which is the one that metastasizes.
We know, again, from post-mortem studies when you type the prostate cancers you also type the metastasis. In other words, the spread to the bone, that you can have a large tumor which goes nowhere and a very small cancer which is the one that has spread to the bone and caused the ultimate demise of the patient.