January 25, 2016
Prostate Cancer Metastasis: New Discoveries
Brady surgeons and scientists are working together, using a surgical technique pioneered by three of our urologists, to target potentially lethal prostate cancer before it has a chance to spread. "The key here involves what we call disseminated tumor cells, or DTCs," explains Ken Pienta, M.D., the Don Coffey Professor of Urology. "We can detect them at the time of radical prostatectomy — these tiny prostate cancer cells that have escaped the prostate and taken up residence in the bone marrow." Important note: DTCs are not the same thing as bone metastases. Just because a man has these cancer cells in his bone marrow doesn't mean that he has cancer growing in his bone, Pienta hastens to point out. The purpose of this story is not to scare anybody, but to tell you about exciting work that has the potential to allow doctors to see into the future, through a microscope, and identify trouble- making cells years before they are able to cause a problem.
At the moment, Pienta and colleagues don't know exactly what to make of these DTCs. "They remain poorly defined," he says, "but we think they are a mixture of passively sloughed, nonlethal cells that are going to die anyway — which means they're nothing to worry about — but in some cases they could also be actively migrating, cancer cells that could eventually develop into clinical metastases. It is very important to study these DTCs so we can determine how to stop the lethal ones. Previously, it was reported that nearly all men have these cancer cells in their bone marrow at the time of surgery. Now we have the know-how to prove how many men have these cancer cells in their bones, so we can go after that cancer."
In laboratory research, Brady resident Michael Gorin has developed sensitive new methods to detect and capture these cells for analysis, Pienta says. And three Brady surgeons — Ashley Ross, Ted Schaeffer, and Alan Partin — have pioneered a painless technique to sample the marrow from the pubic bone just before radical prostatectomy, when the patient is asleep. "This has never been done before and represents an exciting new advance for the field," says Pienta. "The team has already obtained samples from more than 50 men and we are busy characterizing these cells. We expect to study 500 men in the coming year; this will be the largest study ever performed to characterize DTCs in men at the time of surgery."
Pienta and colleagues believe this research will identify the early steps by which lethal prostate cancer "develops and metastasizes to the bone marrow microenvironment, opening the door for early therapeutic intervention to decrease deaths from prostate cancer."