Unplanned radiotherapy equipment downtime: Impact on clinical and organizational operations

Unplanned downtime of radiotherapy equipment represents a critical challenge because it can interrupt clinical workflows, reduce treatment capacity and potentially affect patient outcomes. This study aims to evaluate the organizational and operational impact of unplanned radiotherapy machine downtime across multiple treatment technologies within a high-volume academic centre.

A retrospective observational analysis was conducted to examine all unplanned equipment failures that occurred between January 2019 and December 2024 in a radiotherapy department. Five megavoltage (MV) radiotherapy treatment systems were analysed: one conventional linear accelerator, three tomotherapy systems and one linear accelerator (LINAC) attached to a robotic arm system. Kilovoltage treatment units were not present in the department during the study period. For each failure event, downtime duration, fault category and type of intervention were recorded. Downtime was quantified in hours and weighted according to the average number of treatment sessions delivered per hour on each machine, to estimate the potential number of treatment sessions lost. Descriptive statistics were used to summarise failure patterns and operational impact.

A total of 1537.5 h of unplanned downtime were recorded over the five-year period. Multileaf collimator (MLC) failures were the leading contributors to downtime (359 h), followed by Dose control errors (259 h), LINAC failures (234 h), and facility-related issues (188 h). When weighted by machine-specific productivity, an estimated 4098 treatment sessions corresponded to a theoretical reduction in treatment capacity. Considerable variability in downtime patterns was observed among different technologies, highlighting the influence of system design, workload and maintenance strategies.

Unplanned radiotherapy equipment downtime represents a significant source of organizational inefficiency with measurable clinical and operational consequences. Targeted preventive and predictive maintenance strategies, particularly for MLC and facility-related failure modes, along with investment in specialized technical expertise, may substantially improve service continuity and treatment capacity.

Radiotherapy machines can sometimes break down, which may delay cancer treatment. This study examined equipment failures over five years in a radiotherapy centre and looked at how they affected treatment services. This study found that some types of faults caused large amounts of downtime and reduced the number of treatments that could be delivered. This matters because preventing these problems could improve service reliability and help patients receive treatment without unnecessary delays.