Definitions and principles of focal therapy
Focal therapy is a treatment concept that is quite broad in clinical application, encompassing the spectrum of precise laser ablation of a tumor target to near complete destruction of a large portion of thegland, as long as sexual and urinary function can be preserved. The index lesion, along with any other secondary lesions, needs to be identified and characterized as to itsclinically significance and whether it requires treatment. The target(s) need to be examined within the 3-dimensional space of the prostate, particularly in relation to important anatomical structures, such as theneurovascular bundles and urinary sphincter. Based on these factors, the surgeon then decides the number, location and boundariesofthe targeted ablation zones, weighing the perceived benefits and disadvantages oflesser or greater ablation volume on oncologic and functional outcomes. Applications that employ greater ablation volumes potentially diminish the likelihood of residual/denovotumor in the untreated area(s) but risk, to some degree, the loss of physiologic function depending on location of ablation zones near critical anatomical structures. This chapter outlines the more commonly utilized configurations of focal ablation, to provide a standard nomenclature for reporting andcomparison of clinical outcomes.
