To be honest, the question does not have a clear answer. I read one journal article in which “surgical manipulation” of the prostate gland during radical prostatectomy (RP) increased the number of circulating tumor cells (CTCs, or breakaway tumor cells into blood circulation); it was proven by comparing blood samples before and during surgery. Then I found another journal article showing that robotic assisted RP did not cause an increase in CTCs. Before I go further, here’s what you should know about the chances of cancer spreading on its own.
It is scary to be told, “You have cancer.” No matter how much your doctor reassures you that your cancer is highly treatable, there is always that lurking fear: What if it spreads? You may know of someone who had a malignant tumor removed or radiated—only to find out later that it’s growing somewhere else (metastasis). In fact, it is not easy for cancer to spread because the body is equipped with many defenses against rogue cells. On its own, cancer has to overcome several problems in order to spread. Here are just a few:
- A breakaway cell doesn’t just float free. It has to “crawl” into solid barriers posed by surrounding healthy tissues, where it has to “degrade” those tissues to make room for itself.
- If it manages to penetrate through a blood vessel wall, it is swept into an unfavorable fast-flowing environment where it is more likely to die off or be killed by the immune system.
- If it survives in the bloodstream, it must attach to the inside lining of a blood vessel, from which it has to work its way out into a more favorable “host environment.” If it gets that far, it has to attach to tissues that are different than its home tissues, requiring adaptation.
Of course, it is a reality that some CTCs do get past these and other obstacles in order to implant and clone themselves somewhere else. Science now has the ability to detect CTCs in the blood. Several of these “liquid biopsy” tests are available and more on the way. (Note: they don’t take the place of a needle biopsy.) Low risk prostate cancer tumors may not have detectable CTCs at first, but as a tumor enlarges and becomes more aggressive, the number of CTCs will increase. According to experts, “Circulating tumor cells (CTCs) in the blood stream play a critical role in establishing metastases.”[i] This brings me back to the issue of whether or not RP releases CTCs into the bloodstream during surgery.
As I said at the beginning, there are two sides to the issue. It seems that the more invasive a surgery is, the greater the risk of disturbing the tumor and its blood vessels, thereby aggravating the release of cancer cells. As far as I can tell, no one knows for sure. However, there is a feature of heat-based ablations that works against metastasis, and that is the extreme temperature. This is true of our Focal Laser Ablation (FLA). Burning not only destroys the tissue, it also closes off blood vessels. When the laser is switched on, FLA expands in all directions so rapidly that it quickly encompasses the tumor plus a margin of safety. Unlike a scalpel cutting away tissue, nothing that exists within that globe of heat can survive or break away.
I have not yet encountered any articles on heat ablation and CTCs, but I would certainly welcome the research. In the meantime, I have confidence that the FLA procedure is highly unlikely to spread cancer.
[i] Hong B, Zu Y. Detecting Circulating Tumor Cells: Current Challenges and New Trends. Theranostics. 2013;3(6):377-394. doi:10.7150/thno.5195.