Prostate cancer treatment ranges from active surveillance to prostatectomy, depending on the severity of the disease. But a middle ground is emerging in the form of focal therapy, which aims to replicate the organ preservation approach adopted for several other solid tumors. The goal of focal therapy is to destroy the tumor while minimizing damage to non-cancerous tissue and sparing key structures, such as the neurovascular bundles and external urinary sphincter.
“The idea is that we can eventually achieve adequate cancer control and at the same time we can effectively preserve quality of life,” said Rafael Sanchez-Salas, MD, a staff surgeon at the Institute Mutualiste Montsouris in Paris, France.
Dr. Sanchez-Salas will present the annual Société Internationale d’Urologie (SIU) Lecture during Tuesday’s Plenary I program. His 20-minute presentation, which will begin at 8 a.m. in Hall A in the San Diego Convention Center, is titled Image Guided Therapy for Prostate Cancer: Quo Vadis? Quo vadis is a Latin phrase that roughly translates to “where are you going?”.
Dr. Sanchez-Salas will review conclusions from a recent conference on image guided therapy for prostate cancer sponsored by the SIU and the International Consultation on Urologic Diseases (ICUD). Presenters at the conference reviewed imaging advances and discussed how image guided therapy can be used to treat prostate cancer.
“Imaging has become invaluable for cancer visualization, biopsies, patient selection and posttreatment control,”
Dr. Sanchez-Salas said.
The essential and perhaps the most difficult part of treatment is patient selection because it is based on identifying the so-called index lesions in the context of a multifocal disease, Dr. Sanchez-Salas said. There is a great deal of work under way to improve the random, blind approach for prostatic biopsies, he noted.
Therapeutic imaging options for prostate cancer include cryotherapy and high-intensity focused ultrasound (HIFU). Cryotherapy is considered an alternative therapy by the AUA and the European Association of Urology. HIFU has been used in Europe for many years and was recently approved by the U.S. Food and Drug Administration, not as a treatment for prostate cancer, but as a tool for prostatic tissue ablation.
Non-thermal techniques include irreversible electroporation, photodynamic therapy and focal laser ablation, and targeted radiation therapy (external and brachytherapy). Other therapies include transurethral resection of the prostate, thermal therapy with interstitial microwaves, interstitial radio frequency, thermotherapy with nanoparticles and proton therapy.
According to a summary of the consensus statements from the SIU-ICUD conference, significant volume (≥0.2 cc or ≥7 mm in diameter) of Gleason 3+4 (prognostic grade group 2) within the treated zone is considered failure of focal therapy. In the untreated zone, failure is defined by the development of any foci of clinically significant cancer requiring further therapy. Patients in whom such foci develop within 12 to 18 months of focal therapy likely represent selection failure.
The summary of findings from the conference also concluded that currently there are not enough data to determine appropriate PSA levels with long-term prognosis following focal therapy, and more work needs to be done to determine the optimal follow-up biopsy regimen.
Multiparametric magnetic resonance imaging is a useful tool for follow-up of focal therapy, according to the consensus statement summary, and further focal therapy is recommended “when the reasons for initial failure can be clearly identified and corrected, and both the physician and patient feel this option is reasonable.”
“One of the unknowns about the future of focal therapy is how to clearly incorporate tumor markers and genetics into the selection process for this treatment option,” Dr. Sanchez-Salas said.
Plenary I Preview
Société Internationale d’Urologie (SIU) Lecture
Image Guided Therapy for Prostate Cancer: Quo Vadis?
Rafael Sanchez-Salas, MD
8 – 8:20 a.m. Tuesday
Hall A, San Diego Convention Center