A17 Session 5: General Urology : Role of focal therapy prostate cancer

Abstract

New forms of thermal ablation have emerged over the past few decades to eradicate solid organ cancers. Much of this is due to the propagation of companies and technologies aimed at providing minimally invasive procedures that can be performed in an out-patient setting. In addition, we have learned more about the biology of some of these cancers, and research has demonstrated that the low metastatic rate for many of these indolent tumors make them amenable to ablation. At the end of the last century the introduction of third generation, gas-driven cryotherapy based on the Joule–Thompson effect has completely revolutionized the technique of cryosurgical ablation of the prostate. Recent improvements have allowed a simpler and quicker freeze–thaw process inside the prostate gland that has significantly shortened the operative time. Secondly, the use of ultra thin 17-gauge needles has become a truly minimally invasive procedure with direct transperineal skin penetration and precise insertion of the cryoprobes into the prostate through a conventional brachytherapy-type grid template. Despite these advances, whole-gland prostate cancer treatments can damage intimate anatomical structures (bladder, erectile nerves, rhabdosphincter and rectum) that contribute to a high quality of life. While the incidence of such damage has decreased as techniques to deliver both radiation and surgical extirpation have improved, morbidity remain significant in both frequency and personal impact. The role of organ-preserving therapy—most commonly termed “focal therapy”—has been suggested as a way to eliminate small-volume prostate cancer. The hypothetical premise of focal therapy is that while clinically insignificant smaller tumors may coexist elsewhere in the prostate gland, a dominant tumor drives the biology of the disease; thus, destroying the dominant tumor may alter the natural history of the disease for the individual patient. If focal therapy can destroy the dominant tumor in a way that limits collateral damage to urinary, bowel, and erectile functions associated with other prostate cancer therapies, this form of management may be desirable for well-selected patients who may be willing to accept potential oncological concessions in order to limit these risks. The concept of focal therapy for prostate cancer follows the same treatment paradigm used for almost all other solid tumors, where careful study has revealed that functional outcomes are improved by minimizing the excised or destroyed tissue with no resulting loss of oncologic efficacy. The use of focal therapy to treat kidney and bladder malignancies is well established in the literature. The focus of this lecture will discuss the clinical outcomes of focal therapy in the management of prostate cancer and selecting the proper patients for the procedure. In addition, post-operative management of these patients will be discussed, including functional as well as oncological outcomes.