# A Comparison of Tumor Tracking Accuracy Using Real-Time Adaptive Motion Management on Helical Versus Robotic Radiotherapy Platforms: An Interdisciplinary Study

## TL;DR

This study compares the accuracy of tumor tracking in two radiotherapy systems, finding that robotic CyberKnife systems outperform helical tomotherapy, especially for tumors with complex motion.

## Contribution

The study provides a direct comparison of tumor tracking accuracy between helical and robotic radiotherapy platforms using real-time adaptive motion management.

## Key findings

- CyberKnife showed a mean tumor tracking deviation of 0.8 mm, significantly lower than TomoTherapy's 2.3 mm.
- The difference in tracking accuracy was statistically significant (p < 0.01) for tumors with high motion.
- CyberKnife's superior performance supports its use in precision radiation therapy for complex tumor motions.

## Abstract

Background

Real-time adaptive motion management (RTAMM) systems have enhanced the accuracy of tumor tracking during radiotherapy. This study aimed to investigate the tumor tracking accuracy of helical tomotherapy and robotic CyberKnife systems. The study objective was to assess the tumor tracking accuracy of RTAMM in helical and robotic radiotherapy systems and determine their clinical relevance in treating tumors with complicated motion.

Methodology

This retrospective study analyzed the clinical and imaging data of 60 patients with lung or liver tumors treated with TomoTherapy or CyberKnife between March 2024 and January 2025. Tumor positional deviations were tracked and recorded in real time using onboard imaging. Mean deviations and standard deviations were calculated, and independent t-tests were used to compare tracking accuracy.

Results

CyberKnife demonstrated superior tumor tracking accuracy, with a mean deviation of 0.8 mm (±0.2 mm) versus 2.3 mm (±0.4 mm). CyberKnife outperformed tomotherapy in tumors exhibiting high motion, with a statistically significant difference (p < 0.01).

Conclusions

Robotic CyberKnife systems provide more accurate tumor tracking than helical tomotherapy systems, particularly for tumors with complex motions, validating their use in precision radiation therapy.