In its commitment to tailoring prostate cancer treatment to the needs of each patient, UC San Francisco’s Department of Urology uses focal therapy as an important option for men with clinically significant cancers that are located in one region of the prostate. Focal therapy delivers a finely targeted energy source to destroy cancer cells, while minimizing damage to surrounding tissue. Now, in addition to using cryotherapy, a focal therapy that freezes tumor tissue, UCSF urologic surgeons have added high-intensity focused ultrasound (HIFU) – which uses heat to kill cancer cells – as an option for patients whose cancer diagnosis meets certain criteria.
HIFU is administered through a rectal probe targeting the adjacent prostate gland cancer. High-intensity ultrasound beams are focused to converge on the tumor, heating and destroying cancer cells while sparing adjacent tissue. “This treatment allows urologists to observe the ablation in progress, so they can visualize tumor destruction in real time,” says Katsuto Shinohara, MD, who along with Hao Nguyen, MD, PhD, leads UCSF’s focal-therapy program.
UCSF has offered cryotherapy as a focal therapy option since the early 1990s and was one of the first institutions to use this approach in prostate cancer patients. Shinohara initially used the treatment to ablate the entire prostate gland, and the therapy has since been refined to destroy only tumor cells within the gland. Guided by transrectal ultrasound imaging, a urologist inserts thin metal probes into the prostate through the perineum. The probes are then cooled by argon gas, to freeze cancer tissue.
HIFU offers the promise of precise energy delivery in a completely noninvasive system. “HIFU allows us to match the prostate shape while minimizing sexual dysfunction and urinary incontinence,” says Shinohara. Where many centers offer just one type of focal therapy, UCSF offers two, to allow for treatment to be tailored to each patient’s needs. The UCSF Urology Department also applies its considerable expertise and experience in advanced imaging and biomarkers to further refine which men are most likely to benefit from focal treatment, and to improve and tailor post-ablation monitoring protocols. Focal therapies add to the great wealth of clinical experience with robotic nerve-sparing surgery and with active surveillance by UCSF urologists.
As with all prostate cancer treatments, patient selection is important in focal therapy. A patient’s tumor must be clearly visible on MRI or ultrasound, biopsy-confirmed and confined to only one lobe of the prostate. To minimize the risk of urinary incontinence or sexual dysfunction, tumors should not be too close to the urethra or to the neurovascular bundle that controls sexual function. Focal therapy is also best used in patients whose tumors appear more aggressive on biopsy (Gleason score of 7 or higher), making them poor candidates for active surveillance alone.
Although UCSF is a leader in the use of active surveillance for many early-stage cancers – with urologists advocating surveillance alone for the large majority of men with low-risk disease – the team’s experience has shown that some cancers progress and should be treated. Focal therapy allows well-selected men to have their cancer treated while minimizing side effects. Patients are followed after focal therapy, typically with regular blood tests for PSA monitoring, ultrasound and MRI imaging, and on occasion prostate biopsies.
“We want to offer our patients state-of-the-art treatments for their specific clinical condition,” says Raj S. Pruthi, MD, MHA, FACS, Professor and Chair of the Department of Urology at UCSF. “Prostate cancer presents differently in each patient. Our growing focal therapy options allow us to find and personalize treatment for each individual. UCSF is committed to exploring new technologies to provide comprehensive, innovative and patient-centered care that balances long-term survivorship with optimal quality of life.”