Identifying predictive parameters for failure of DQA in patient using helical tomotherapy planning

Authors

  • Wanwisa Bumrungpagdee Radiotherapy Unit, Department of Radiology, Buddhachinaraj Phitsanulok Hospital
  • Chawalit Lakdee Radiotherapy Unit, Department of Radiology, Buddhachinaraj Phitsanulok Hospital

Keywords:

Helical tomotherapy, pre-treatment delivery quality assurance (DQA), intensity-modulated radiation therapy (IMRT) planning, predictive model for DQA

Abstract

Background: Radiation therapy using helical tomotherapy requires pre-treatment delivery quality assurance (DQA) to verify treatment accuracy. However, in certain urgent situations such as patients requiring radiation to stop bleeding, those receiving radiation for pain relief, or those with a strictly scheduled treatment course where DQA cannot be performed immediate treatment planning and delivery are necessary without DQA verification.

Objective: To identify predictors associated with DQA failure and to develop a predictive model for pre-treatment DQA in helical tomotherapy.

Materials and Methods: Data were retrospectively collected from treatment plans stored in the Accuray Precision system. The data included the following parameters: treatment sites (Head and Neck, Brain, Chest, Abdomen, and Pelvis), fraction dose, target volume, field width (1 cm, 2.5 cm, 5 cm), pitch, modulation factor (planned and actual), gantry rotations, gantry period, beam-on time, couch travel, couch speed, fraction monitor units (MUs), and leaf open time parameters (maximum, minimum, mean, mode, and standard deviation). All data were obtained from the Radiation Oncology Unit, Department of Radiology, Buddhachinaraj Hospital, Phitsanulok, between January 2020 and December 2023. Predictive factors for delivery quality assurance (DQA) failure prior to treatment delivery were analyzed using odds ratios (ORs) derived from logistic regression analysis with stepwise backward selection.

Results: Predictors significantly associated with DQA failure requiring treatment re-planning included: pelvic treatment sites (OR 2.91, 95% CI 1.52-5.57), field width of 2.5 cm (OR 0.25, 95% CI 0.07-0.91), beam on time (OR 0.99, 95% CI 0.99-0.99), couch speed (mm/sec) (OR 0.14, 95% CI 0.32-0.60), leaf open time (mode) (OR 0.99, 95% CI 0.99-1.00), and leaf open time (std) (OR 1.02, 95% CI 1.01-1.04).

Conclusion: The predictors obtained from this study can be applied to improve the efficiency of treatment planning, reduce the necessity of repeating pre-treatment quality assurance, and shorten the waiting time in cases where re-planning is required, especially in urgent situations where quality assurance cannot be performed. Therefore, they serve as tools to support clinical decision making more rapidly and accurately.

References

Mackie TR, Balog J, Ruchala K, Shepard D, Aldridge S, Fitchard E, et al. Tomotherapy. Seminars in radiation oncology. 1999;9:108–17.

Chang KH, Ji Y, Kwak J, Kim SW, Jeong C, Cho B, et al. Clinical Implications of High Definition Multileaf Collimator (HDMLC) Dosimetric Leaf Gap (DLG) Variations. Prog Med Phys. 2016;27:111.

Cho B. Intensity-modulated radiation therapy: a review with a physics perspective. Radiat Oncol J. 2018;31;36:1–10.

Chang KH, Lee S, Jung H, Choo YW, Cao YJ, Shim JB, et al. Development of a 3D optical scanner for evaluating patientspecific dose distributions. Physica Medica. 2015;31:553–9.

Thiyagarajan R, Nambiraj A, Sinha SN, Yadav G, Kumar A, Subramani V, et al. Analyzing the performance of ArcCHECK diode array detector for VMAT plan. Rep Pract Oncol Radiother. 2016;21:50–6.

Cao YJ, Lee S, Chang KH, Shim JB, Kim KH, Park YJ, et al. Patient performancebased plan parameter optimization for prostate cancer in tomotherapy. Medical Dosimetry. 2015;40:285–9.

Shimizu H, Sasaki K, Tachibana H, Tomita N, Makita C, Nakashima K, et al. Analysis of modulation factor to shorten the delivery time in helical tomotherapy. J Appl Clin Med Phys. 2017;18:83–7.

Skórska M, Piotrowski T. Optimization of treatment planning parameters used in tomotherapy for prostate cancer patients. Physica Medica. 2013;29:273–85.

De Kerf G, Van Gestel D, Mommaerts L, Van den Weyngaert D, Verellen D. Evaluation of the optimal combinations of modulation actor and pitch for Helical TomoTherapy plans made with TomoEdge using Pareto optimal fronts. Radiat Oncol. 2015;10:191.

Binny D, Lancaster CM, Harris S, Sylvander SR. Effects of changing modulation and pitch parameters on tomotherapy delivery quality assurance plans. J Appl Clin Med Phys. 2015;16:87–105.

Thomas SJ, Geater AR. Implications of leaf fluence opening factors on transfer of plans between matched helical tomotherapy machines. Biomed Phys Eng Express. 2017;4:017001.

Boyd R, Jeong K, Tomé WA. Determining efficient helical IMRT modulation factor from the MLC leaf-open time distribution on precision treatment planning system. J Appl Clin Med Phys. 2019;20:64–74.

Binny D, Lancaster CM, Byrne M, Kairn T, V. Trapp J, Crowe SB. Tomotherapy treatment site specific planning using statistical process control. Physica Medica. 2018;53:32–9.

Chang KH, Lee YH, Park BH, et al. Statistical analysis of treatment planning parameters for prediction of delivery quality assurance failure for helical tomotherapy. Technol Cancer Res Treat. 2020; 19:1533033820979692.

Valdes G, Scheuermann R, Hung CY, Olszanski A, Bellerive M, Solberg TD. A mathematical framework for virtual IMRT QA using machine learning. Med Phys. 2016;43:4323–4334.

Lam D, Zhang X, Li H, Yang D, Schott B, Zhao T, et al. Predicting gamma passing rates for portal dosimetry–based IMRT QA using machine learning. Med Phys. 2019;46:4666–4675.

Bresciani S, Miranti A, Di Dia A, Maggio A, Bracco C, Poli M, Di Spirito D, Gabriele P, Stasi M. A pre-treatment quality assurance survey on 384 patients treated with helical intensity-modulated radiotherapy. Radiother Oncol. 2016;119:60–65.

Westerly DC, Soisson E, Chen Q, Woch K, Schubert L, Olivera G, Mackie TR. Treatment planning to improve delivery accuracy and patient throughput in helical tomotherapy. Int J Radiat Oncol Biol Phys. 2009;74:1290–1297.

Kim J, Kay CS, Jang HS, Kang YN. Analysis of the Effect of Tomotherapy Plan Parameters on Patient-Specific Delivery Quality Assurance (DQA). J Korean Phys Soc. 2019;75:1043–1047.

Binny D, Lancaster CM, Byrne M, Kairn T, Trapp JV, Crowe SB. Tomotherapy treatment site specific planning using statistical process control. Phys Medica. 2018; 53:32–39.

Levin R, Aravkin AY, Kim M. Patientspecific Quality Assurance Failure Prediction with Deep Tabular Models medRxiv. 2022 Oct 4.

Cavinato S, Bettinelli A, Dusi F, Fusella M, Germani A, Marturano F, Paiusco M, Pivato N, Rossato MA, Scaggion A.Prediction models as decision-support tools for virtual patient-specific quality assurance of helical tomotherapy plans. Physics and Imaging in Radiation Oncology. 2023;26:100435

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Published

2025-12-01

How to Cite

1.
Bumrungpagdee W, Lakdee C. Identifying predictive parameters for failure of DQA in patient using helical tomotherapy planning. J Thai Assn of Radiat Oncol [internet]. 2025 Dec. 1 [cited 2026 Jan. 11];31(2):R13-R29. available from: https://he01.tci-thaijo.org/index.php/jtaro/article/view/278943

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