Pathology of prostate cancer and focal therapy ('male lumpectomy').

Focal therapy of the prostate is defined as prostate gland ablation aiming at eradication of unifocal low-risk prostate cancer, and preserving uninvolved (peri-) prostatic tissue and therefore quality of life. The major arguments against focal therapy can be classified under the headings of understaging and multifocality. The argument of understaging highlights the importance of the occasional, but troublesome, finding of a large, extraprostatic or high-grade tumor (Gleason score > or = 7) in about a quarter of radical prostatectomy specimens removed from men initially classified as having a low-risk tumor. Indeed, 85% of all prostate cancer cases are multifocal. These concerns can be offset by additional testing: another biopsy, especially a transperineal mapping biopsy, and magnetic resonance imaging (MRI) of the prostate. The technology needed to ablate small regions or sectors of the prostate harboring a known cancer is rapidly becoming available. Cryotherapy is already being used and the preliminary data are encouraging, Ultrasound-guided high-intensity focused ultrasound (HIFU), photodynamic therapy using newly developed light-sensitizing agents, and MRI-guided HIFU are all promising new tools.