KEY POINTS
- Technical note describing an automated Python pipeline integrated with MOSAIQ oncology information system for institutional volumetric modulated arc therapy plan-complexity surveillance.
- The cohort included 3,751 clinically approved volumetric modulated arc therapy plans from March 2023 to March 2026, across 20 dosimetrists and 15 radiation oncologists.
- Patient-specific quality assurance records were matched for 3,402 of 3,751 plans (90.7%); mean gamma pass rate was 98.7%, median was 99.6%, and 115 plans (3.4%) fell below 95%.
- All complexity metrics correlated significantly with patient-specific quality assurance pass rate; aperture irregularity was the strongest negative predictor (ρ = -0.358) and modulation complexity score for volumetric modulated arc therapy was the strongest positive predictor (ρ = +0.336).
- Monaco plans had higher monitor unit factor than Pinnacle3 plans (+32%, p < 0.001) but also higher mean patient-specific quality assurance pass rate (99.0% versus 98.5-98.6%); linac-level pass rates varied from 97.3% to 99.2%.
CLINICAL TAKEAWAY
This study supports routine, oncology information system-integrated plan-complexity surveillance as a practical quality assurance layer for large volumetric modulated arc therapy programs. The main operational message is that complexity thresholds should probably be stratified by treatment planning system, site, and linac rather than interpreted as one universal institutional number. The evidence is useful but local: single institution, Elekta linac fleet, archival composite-dose quality assurance, and modest correlations between individual complexity metrics and pass rate.