[P274] A failure mode and effect analysis of deep inspiration breath-hold for left-sided breast cancer radiation therapy

Purpose The aim of this study was to assess the possible failure modes and analyze their consequences and effects in deep inspiration breath-hold radiation therapy. Methods Failure modes and effects analysis (FMEA) is step-by-step approach for identifying all possible failures in a process. Each step of the patient pathway for deep inspiration breath-hold radiation therapy was defined and four major process steps were created: patient initial clinical assessment, CT simulation, treatment planning and treatment delivery. For each process step 4–16 potential failure modes and effects were identified by the multidisciplinary team responsible for the FMEA. Each potential failure mode was scored for the likelihood of occurrence, potential severity and how easily it can be detected, depending on current departmental controls. Risk priority numbers (RPNs) were calculated as the product of occurrence, severity and detectability based on Task Group (TG)-100 scale [1] . Results RPNs were ranked from highest to lowest. Online imaging registration and patient positioning correction during treatment delivery, patient positioning and immobilization and patient preparation and coaching for deep inspiration breath-hold had the highest RPN 378, 210 and 168, respectively. Treatment planning check by a second medical physicist, patient positioning and set up instructions in the oncology information system had the lowest RPN score 10 and 32, respectively. Conclusions TG-100 recommends that FMEA can be used as a tool for risk and hazard analysis. An FMEA evaluation of deep inspiration breath-hold for left-sided breast cancer treatment can identify significant improvements in processes and increase in quality and safety of treatment delivery. Process steps with the highest RPNs must be addressed and new procedures must be introduced to minimize possible failures.