E. David Crawford, MD
Professor, Surgery and Radiation Oncology, Head, Urologic Oncology, University of Colorado, Anschutz Medical Campus, Aurora, CO
Prostate-specific antigen (PSA) testing often detects smallvolume tumors, but it cannot determine the aggressiveness of the cancer. This leaves patients with a difficult decision between active surveillance and definitive treatment with surgery and/or radiation.
An emerging technique known as targeted focal therapy now offers some patients with localized prostate cancer a middle ground between these two options, according to E. David Crawford, MD, professor of Surgery and Radiation Oncology, head of the Section on Urologic Oncology, University of Colorado Health Sciences Center in Denver.
Referred to as the “male lumpectomy,” targeted focal therapy treats only the tumor cells, not the entire prostate. The procedure begins with a three-dimensional (3D) mapping biopsy, which identifies the location of the tumor cells within the prostate. Once the cancer is located, there are multiple methods available to destroy the tumor cells, including cryotherapy, high-intensity focused ultrasound, intensity-modulated radiation therapy, brachytherapy, and photodynamic therapy.
During the 5th Annual Interdisciplinary Prostate Cancer Congress in New York City in March, Crawford discussed the potential for targeted focal therapy as an effective option.
Although he supports PSA testing, Crawford said its inability to determine which tumors require treatment frequently leaves patients and physicians in a difficult predicament. Small-volume tumors are often detected, but with no accompanying knowledge of which tumors are indolent, the course of action is unclear.
He said that active surveillance is given a lot of “lip service,” but that studstudies have shown its use has actually decreased over time. Patients are often unwilling to do nothing when they know they have a tumor inside them. Given this reality, he said that targeted focal therapy offers some men with localized tumors a solution between active surveillance and definitive treatment with surgery and/or radiation.
The Cryocare CS Surgical System is utilized in cryotherapy. It delivers cold temperatures to targeted tissue, monitors temperatures in the surrounding tissue, and captures images of the affected areas. The system was developed by Endocare, a subsidiary of Texas-based HealthTronics, Inc.
Crawford further discussed the targeted focal therapy approach in this interview with OncologyLive
OncologyLive: How do you determine which patients are eligible for targeted focal therapy?
: If we set the stage, what we know is that in men who undergo biopsies, 30% to 50% of them will have cancers that are deemed at least “low risk” on the initial biopsy. Low risk would be somebody with a PSA that’s less than 10 and a Gleason score of 6 in one or two cores, not involving more than 20% of the cores. I would say that describes anywhere between 20% and 50% of the patients that we see with prostate cancer. And so, for these individuals, rather than rush into surgery or active surveillance, we recommend first getting more information.
In every other cancer that we treat, we get more information. For example, we get bone scans and PET scans in lung cancer and breast cancer. However, in prostate cancer with a low PSA, PET scans and bone scans are a waste of time because they are looking for metastatic disease. We want to know what’s going on in that prostate. We want to know whether this is a cancer that we can just watch, a cancer in which we can just treat a small area of the prostate where the cancer is located, or a cancer that requires more aggressive treatment. And so that’s where the 3D-mapping biopsies come in.
With mapping biopsies, we go in transperineally, under the scrotum directly into the prostate. By going transperineally, our risk of infection has been very low and we’re able to sample the whole prostate, unless it’s huge, and then the pubic arches are in the way so we can’t get there. But if you have a prostate that’s 40 to 90 grams, with 90 grams being a large prostate, we can get the whole thing.