Focal laser ablation as clinical treatment of prostate cancer: report from a Delphi consensus project.

PURPOSE: To define the role of focal laser ablation (FLA) as clinical treatment of prostate cancer (PCa) using the Delphi consensus method. METHODS: A panel of international experts in the field of focal therapy (FT) in PCa conducted a collaborative consensus project using the Delphi method. Experts were invited to online questionnaires focusing on patient selection and treatment of PCa with FLA during four subsequent rounds. After each round, outcomes were displayed, and questionnaires were modified based on the comments provided by panelists. Results were finalized and discussed during face-to-face meetings. RESULTS: Thirty-seven experts agreed to participate, and consensus was achieved on 39/43 topics. Clinically significant PCa (csPCa) was defined as any volume Grade Group 2 [Gleason score (GS) 3+4]. Focal therapy was specified as treatment of all csPCa and can be considered primary treatment as an alternative to radical treatment in carefully selected patients. In patients with intermediate-risk PCa (GS 3+4) as well as patients with MRI-visible and biopsy-confirmed local recurrence, FLA is optimal for targeted ablation of a specific magnetic resonance imaging (MRI)-visible focus. However, FLA should not be applied to candidates for active surveillance and close follow-up is required. Suitability for FLA is based on tumor volume, location to vital structures, GS, MRI-visibility, and biopsy confirmation. CONCLUSION: Focal laser ablation is a promising technique for treatment of clinically localized PCa and should ideally be performed within approved clinical trials. So far, only few studies have reported on FLA and further validation with longer follow-up is mandatory before widespread clinical implementation is justified.

MR imaging-guided prostate interventional imaging: Ready for a clinical use?

Prostate interventional magnetic resonance imaging (MRI) is now routinely performed in many centers. Its more widespread acceptance is limited by the cost of the use of MRI largely related to the long duration time of the procedures. However, the benefit of a robotic assistance has generated a new interest, because it substantially shortens the procedure time, while improving the accuracy. MRI-guided biopsy is considered as an appealing alternative to transrectal ultrasound (TRUS)-guided fusion biopsy, given the limitations of TRUS-MRI image registration systems. MRI-guided focal treatment also benefits from robotic assistance and from the unique property of MRI, which allows the measurement of the temperature in real-time during tumor ablation. The transrectal and transperineal approaches can be used and the respective indications of each pathway will depend on several factors, including the location of the tumor and the examination time, which will condition the occupation time of the MR room, a major factor influencing the overall cost of MRI-guided procedures. This review addresses the current practice of prostate MRI-guided interventional procedures and potential future applications.

Controlling the Ground Reaction Force During Lifting.

The control of the ground reaction force vector relative to the center of gravity (CoG) was examined while subjects performed a back-lifting task. Six male subjects (aged 24.0 +/- 2.5 years) repeatedly lifted a barbell. A biomechanical analysis that used a linked segment model revealed that the summed rotations of body segments during lifting yielded a specific rate of change of the angular momentum of the entire body. This equaled the external moment provided by Fsubg; relative to CoG. This implies that multisegment movements involve control of the angular momentum of the entire body through an appropriately directed Fsubg;. Thus, in dynamic tasks Fsubg; is pointed away from rather than lined up with the CoG, as is the case in static tasks.