Robot‐assisted <scp>MRI</scp> / <scp>US</scp> fusion transperineal prostate biopsy using the Biobot system: a single‐centre experience

Abstract

Treatment decisions for prostate cancer (PCa) still rely on histological confirmation from a biopsy [1]. In today's precision medicine era, cutting-edge technologies are revolutionising clinical practice. Although the potential of robotic surgery in urology is widely acknowledged, the possibility of robot-assisted prostate biopsies (RA-PBx) remains largely unexplored [2]. Newly available RA-PBx systems, such as the Biobot Mona Lisa (Biobot Surgical, Singapore), combine robotic precision with the transperineal approach, offering accurate PCa mapping, efficient site storage, and potential benefits for focal treatments [3, 4]. Moreover, they promise lower complication and infective rates, as well as improved patient comfort by enabling a minimally invasive sampling process that requires only two puncture sites [5-7]. This study aims to demonstrate the RA-PBx process using the Biobot platform and to evaluate its feasibility and safety. Between July 2023 and July 2024, 44 consecutive patients with suspected PCa underwent a transperineal RA-PBx using the second generation of the Biobot MRI/TRUS fusion system. If clinically feasible, multiparametric MRI (mpMRI) was performed on patients prior to the biopsy. mpMRI was conducted and analysed according to the Prostate Imaging Reporting and Data System (PI-RADS)-v2 classification system [8]. Before RA-PBx, both the prostate and the target lesions identified on MRI are segmented in the Biobot software. On the day of the biopsy, the patient is placed in the lithotomy position under sedation or general anaesthesia with laryngeal mask and receives antimicrobial prophylaxis. The Biobot system is then set up. This system requires an external ultrasound device; in this study, the BK 5000 ultrasound system with the 9048 high-resolution biplane transducer (BK Medical, Burlington, MA, USA) was used. The Biobot system consists of two main components: the control system and the robotic arm. The control system, operated via a touch-screen monitor, allows for biopsy planning and continuous monitoring of the procedure. The software-controlled robotic arm, with its multiple joints, first facilitates manual positioning of the ultrasound probe in the patient's rectum to achieve an optimal view of the prostate, followed by RA-PBx execution (Fig. 1). The software guides the surgeon through several steps, starting with setting the prostate's apical and base limits. It then scans the prostate every 0.5 mm to generate a three-dimensional ultrasound visualisation. After segmentation, the surgeon can refine the model by adjusting the segmentation markers. Once biopsy planning is complete, the system positions the device to align the biopsy needle track with the target area specified in the software, using the skin as the centre of rotation. The clinician manually inserts the biopsy needle (Bard Max Core, Tempe, AZ, USA) to the required depth defined by the system without requiring any needle or sheath and acquires the biopsy sample. The system autonomously adjusts the needle's angle and depth to ensure precise and reproducible biopsies. Unlike techniques that use a coaxial needle, this system punctures the skin for each biopsy sample. However, the procedure is still completed with only two perineal access points, one per hemigland (see accompanying Video S1). When the pathological results become available, a dedicated software platform facilitates the review of the biopsy findings. By selecting the positive tumour cores, the system visually displays these cores within the prostate (Fig. 2). This enhances understanding of the tumour's location, which can be valuable for planning future focal treatments if clinically indicated. Data were retrospectively collected. For each patient, demographic information, urological history, MRI data, biopsy details, peri-operative complications, and treatment actions were recorded. Data are presented as medians with interquartile ranges for continuous variables and as relative f