Automated High-Dose Sphere Placement in Photon Lattice Radiation Therapy: A Systematic Review

Introduction: Lattice Radiation Therapy (LRT) is an evolving spatially fractionated radiation therapy (SFRT) technique that delivers heterogeneous dose distributions to large and radioresistant tumors. The literature highlights LRT’s potential for effective tumor debulking, palliation, and immune modulation. Effective LRT planning is crucial for maximizing tumor control while minimizing toxicity to organs at risk (OARs). The process involves defining the size, spacing, and arrangement of high-dose vortexes within the GTV. Traditionally, this has been a manual and time-consuming process, prone to inter-planner variability in vortex placement. Recent research has focused on developing automated or semi-automated tools to address these challenges, enhancing planning standardization. We aimed to systematically review for the first time the available scientific evidence of automated planning tools of vortexes for Lattice Radiotherapy and to assess the efficacy of such tools for standardizing Lattice Radiotherapy delivery. Methods: A systematic review of available studies in PubMed, Web of Science, and Scopus, including the terms “Lattice radiation therapy and (automated or optimized)”. Only LRT clinical planning reports published in English and with access to the full accepted text were considered eligible. This study was conducted in accordance with the PRISMA guidelines and was registered on the PROSPERO platform (CRD420251108024). Results: A total of 82 articles were found. Twenty articles fulfilled all inclusion criteria. Automated treatment planning tools have significantly improved the efficiency, consistency, and scalability of LRT planning, addressing limitations of manual planning. In conclusion, LRT should be planned to use automated tools to improve wide clinical standardization and implementation.