In April, 2010 the Medscape/Urology website posted an article from the journal Future Oncology.i The article posed a crucial question as to whether focal therapy is becoming a standard of care for localized prostate cancer and if so, by what criteria? After thoughtfully reviewing the literature and exploring key determinants, the authors concluded that there is indeed a future for focal treatment.
Focal therapy is intended as a middle ground between no treatment vs. radical (whole-gland) treatment. A growing number of younger men are being screened and diagnosed with early stage, moderate risk cancer. They face a dilemma. Radical treatments have a 50% rate of side effects, referred to as "treatment burden", while active surveillance carries monitoring responsibilities, a psychological burden, and the risk of progression.
Regarding the problem of treatment burden, the authors point out that efforts have been made to reduce the impact of radical therapies with either robotics (surgery) or intensity modulated radiotherapy. "However, these treatments are associated with high capital and considerable recurrent costs. In addition, it is generally agreed that the toxicity profile has altered very little," say the authors. Therefore, clinicians are seeking ways to direct treatment just to the cancer plus a safety margin, while preserving as much healthy tissue as possible and sparing key urinary and neurovascular structures. This reflects a noteworthy trend in managing other cancers for functional preservation (breast, kidney, colon and lung).
How many men are potentially candidates for focal therapy? Due to increased screening, approximately 20-40% of newly diagnosed patients have unilateral disease (more than one tumor focus on only one side of the gland), and 10-44% have unifocal disease (only one tumor focus). A review of retrospective data on unilateral cases where only the cancerous side of the gland was destroyed (ablated) by either cryotherapy or HIFU (high intensity focused ultrasound) showed impotence rates of 10-15% and little to no incontinence.
This is a truly significant reduction in treatment burden.
The key to identifying appropriate candidates for focal treatment is accurate diagnosis. The authors discuss several means of imaging, including technologies that fuse more than one type of technology for real-time imaging, as having great promise for pinpointing clinically significant lesions, meaning of a large enough size to warrant focal treatment at the time of diagnosis. In addition, the article discusses the importance of determining Gleason grade, which can only be done through biopsy, for further determination of the nature of the malignancy.
The article gives valuable information on the meaning of "clinical significance" and explains various approaches to focal treatment (hemiablation, unifocal ablation, and focal ablation.) It also identifies the most common ablation technologies that can be applied to focused ablation (cryotherapy, HIFU and photodynamics) and points out that other technologies are in various stages of testing and use.
The authors conclude, "Ultimately, if there is a consistent finding that the burden of treatment can be significantly reduced, it is likely that patient choice will dictate its true role within the urology and oncology clinic." In short, this article is highly valuable for newly diagnosed prostate cancer patients, especially younger men with active lifestyles, who are interested in focal therapy. There is great merit in reading the entire piece at http://www.medscape.com/viewarticle/717471. For those wishing to pursue this treatment option, there is equal merit in arranging a consultation with a physician who has extensive experience with ablation technologies and access to state-of-the-art, image-guided biopsy equipment such as Artemis (Eigen). A high degree of confidence in the diagnosis and tumor location, and a high degree of trust in the practitioner, are pointers to a successful focal treatment experience.
i Hashim U &o; Emberton M. Is focal therapy the future for prostate cancer? Future Oncology. February 2010;6(2):261-8.