Phil’s response is good. My MRI was Pi-rads 4 & showed a single lesion. I wanted to know what was there. My fusion biopsy identified all six cores in that lesion as cancerous. The other 12 random cores in my prostate were negative. I then had a PSMA scan to ensure it had not spread. That gave me the confidence to go forward with Tulsa Pro and I could not be happier at this point.

Unfortunately, there is no definitive answer to your question involving micro-metastasis although some studies suggest that it does rarely happen; the frequency and the outcomes are currently unknown. But biopsies are like vaccines in a life threatening pandemic: your chances of dying or becoming seriously ill from the disease are exponentially higher than from the vaccine. In life, you have to take educated risks, no way around it.
Current biopsy techniques are very focused and targeted and do not rely on a “pin the tail on the donkey” model to extract the tissue necessary for analysis.

I just wanted to give you a another perspective on your decision.

I am a retired Interventional Radiologist. Most people don't know what that is but for 40+ years I not only interpreted CTs, MRIs, PET scans, plain films etc, but I spent most of my time performing various procedures such as tumor ablations, kyphoplasty (repairing vertebral fractures), angioplasty, various other procedures and (relavent to this discussion) biopsies. Over the course of my career I biopsied thousands of lesions is virtually every organ of the body-including the prostate gland. There is no scientific evidence that needle biopsy seeds the tract or releases tumor cells in the body. It is difficult for cancer cells to grow outside their immediate environment. The vast majority of cancer cells that escape the primary tumor by lymph or vascular access die without their vascular supply and most are destroyed by the body's immune system. If a cancer cell was "pulled" out of the tumor and deposited along the needle tract, it would almost certainly die as it would have no immediate access to nutrients. The body is a hostile environment for foreign invaders or cancer cells outside of the primary tumor.

Here is a synopsis of my story. Of course, it is a sample of one so it may not apply to you. In 2019, as part of my routine physical exam, my PSA bumped up from around 4 to 5.6. Anything greater than a 20% year over year rise is concerning. I saw a urologist who did a digital exam and felt nothing. I had an MRI on our new 3T machine and it showed no enhancing lesions-essentially negative. I sent a blood sample to Mayo Clinic for fractionation and it was sent back "no fractionation performed as PSA < 4, normal for age". My urologist offered a biopsy but I declined and opted for a 6 month PSA followup. MY PSA declined into the 4 range 6 months later.
At my next annual physical my PSA had increased to 7.5. Back to the urologist who said let's repeat the MRI to see of there is anything new but I'm insisting on a biopsy no matter the results. The MRI showed a new enhancing nodule contained within the gland without evidence of spread. The biopsy revealed a high grade cancer, G8, at the site of the nodule.

I opted for a RP. Six months later my PSA went up to 0.37 and a PSMA PET revealed a solitary met at T8. I had successful SBRT (radiation) to that vertebral body that killed the met. Unfortunately, the next PSA 4 months later had increased to 4.6, rapid doubling. New PET revealed a new pelvic node (another met).

I consulted with a very experienced MO at JH and had immediate triple therapy followed by pelvic radiation. PSA went quickly undetectable and has thankfully stayed there for more than 2 years. Off all treatment meds now.

Medical decisions should be made on risk vs reward. You have an elevated PSA with a suspicious nodule in your prostate with a reasonable possibility it is a cancer. Enhancing nodules within the prostate (or other organs) have a good probability of being high grade tumor. The risk of a biopsy (in skilled hands) is fairly low. Your concern about releasing cancer cells is not scientifically proven. But if you do have a cancer there is a chance that it will continue to grow and possibly spread. It does not have to breach the capsule to spread by the vascular or lymph system.

In retrospect, I wish I had been more aggressive earlier and had a biopsy. It may have prevented the spread of cancer elsewhere.

Of course, any decisions related to biopsy or treatment are yours alone. But make this decisions based on facts. I wish you the best.