Influence of Modulation Factor on Treatment Plan Quality and Irradiation Time in Hippocampus-Sparing Whole-Brain Radiotherapy Using Tomotherapy

Akihiko Ishibashi, Hiromasa Kurosaki, Kosei Miura, Nobuko Utsumi, Hideyuki Sakurai, Akihiko Ishibashi, Hiromasa Kurosaki, Kosei Miura, Nobuko Utsumi, Hideyuki Sakurai

Abstract

Objectives: Hippocampus-sparing whole-brain radiotherapy (HS-WBRT) using tomotherapy is known to provide a better dose distribution than volumetric-modulated arc therapy but requires an extended irradiation time. The present study aimed to investigate whether irradiation time can be shortened by reducing the modulation factor (MF) without losing the target dose distribution. Methods: Using six tilted computed tomography images in the head area, the planning target volume (PTV) and hippocampal doses, and the irradiation time was investigated with a jaw width of 1 cm, a pitch of 0.200, and the MF changed from 3.0 to 2.6, 2.2, 1.8, and 1.4. Results: No significant changes in the PTV or hippocampus were found with MF in the range from 3.0 to 1.8, but marked deterioration was found with that of 1.4. The irradiation time showed a linear relationship with the MF within the range from 3.0 to 1.8, with 1334, 1158, 986, and 817 s at modulation factors of 3.0, 2.6, 2.2, and 1.8, respectively. However, when the MF was 1.4, the irradiation time was 808 s. Conclusions: When HS-WBRT is performed with a tilted body position and a jaw width of 1 cm, with a MF of 1.8, a favorable balance between dose parameters and irradiation time is achieved, whereas with a MF of 1.4, the quality of the radiotherapy plan deteriorates, and the irradiation time is approximately the same as that with a MF of 1.8.

Trial registration: ClinicalTrials.gov NCT01780675 NCT02635009 NCT02397733.

Keywords: brain metastases; hippocampus-sparing; tilt heading; tomotherapy; whole-brain radiotherapy.

Conflict of interest statement

Declaration of Conflicting Interests: The authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Figures

Figure 1.
Figure 1.
Example of a dose-volume histogram (case 3).
Figure 2.
Figure 2.
Irradiation time due to change in modulation factor (error bars: standard deviation).

References

    1. Gondi V, Pugh SL, Tome WA, et al. Preservation of memory with conformal avoidance of the hippocampal neural stem-cell compartment during whole-brain radiotherapy for brain metastases (RTOG 0933): a phase II multi-institutional trial. J Clin Oncol. 2014;32(34):3810-3816. doi:10.1200/JCO.2014.57.2909
    1. Caine C, Deshmukh S, Gondi V, et al. Cogstate computerized memory tests in patients with brain metastases: secondary endpoint results of NRG oncology RTOG 0933. J Neurooncol. 2016;126(2):327-336. doi:10.1007/s11060-015-1971-2
    1. Brown PD, Gondi V, Pugh S, et al. Hippocampal avoidance during whole-brain radiotherapy plus memantine for patients with brain metastases: phase III trial NRG oncology CC001. J Clin Oncol. 2020;38(10):1019-1029. doi:10.1200/JCO.19.02767
    1. Yang WC, Chen YF, Yang CC, et al. Hippocampal avoidance whole-brain radiotherapy without memantine in preserving neurocognitive function for brain metastases: a phase II blinded randomized trial. Neuro Oncol. 2021;23(3):478-486. doi:10.1093/neuonc/noaa193
    1. Lin SY, Yang CC, Wu YM, et al. Evaluating the impact of hippocampal sparing during whole brain radiotherapy on neurocognitive functions: a preliminary report of a prospective phase II study. Biomed J. 2015;38(5):439-449. doi:10.4103/2319-4170.157440
    1. Rodríguez de Dios N, Couñago F, López JL, et al. Treatment design and rationale for a randomized trial of prophylactic cranial irradiation with or without hippocampal avoidance for sclc: premer trial on behalf of the oncologic group for the study of lung cancer/spanish radiation oncology group-radiation. Clin Lung Cancer. 2018;19(5):e693-e697. doi:10.1016/j.cllc.2018.05.003
    1. Rong Y, Evans J, Xu-Welliver M, et al. Dosimetric evaluation of intensity-modulated radiotherapy, volumetric modulated arc therapy, and helical TomoTherapy for hippocampal-avoidance whole brain radiotherapy. PLoS One. 2015;10(4):1-12. doi:10.1371/journal.pone.0126222
    1. Gondhowiardjo S, Nurhadi H, Auzan M, et al. Dosimetry analysis on IMRT, VMAT, and HT technique in hippocampal sparing whole-brain radiotherapy. Onkol i Radioter. 2019;46(1):58-63.
    1. Jiang A, Sun W, Zhao F, et al. Dosimetric evaluation of four whole brain radiation therapy approaches with hippocampus and inner ear avoidance and simultaneous integrated boost for limited brain metastases. Radiat Oncol. 2019;14(1):1-8. doi:10.1186/s13014-019-1255-7
    1. Shen J, Bender E, Yaparpalvi R, et al. An efficient Volumetric Arc Therapy treatment planning approach for hippocampal-avoidance whole-brain radiation therapy (HA-WBRT). Med Dosim. 2015;40(3):205-209. doi:10.1016/j.meddos.2014.11.007
    1. Sood S, Pokhrel D, McClinton C, et al. Volumetric-modulated arc therapy (VMAT) for whole brain radiotherapy: not only for hippocampal sparing, but also for reduction of dose to organs at risk. Med Dosim. 2017;42(4):375-383. doi:10.1016/j.meddos.2017.07.005
    1. Yuen AHL, Wu PM, Li AKL, Mak PCY. Volumetric modulated arc therapy (VMAT) for hippocampalavoidance whole brain radiation therapy: planning comparison with Dual-arc and Split-arc partial-field techniques. Radiat Oncol. 2020;15(1):42. doi:10.1186/s13014-020-01488-5
    1. Miura K, Kurosaki H, Utsumi N, Sakurai H. Use of a head-tilting baseplate during tomotherapy to shorten the irradiation time and protect the hippocampus and lens in hippocampal sparing-whole brain radiotherapy. Technol Cancer Res Treat. 2021;20:1-5. doi:10.1177/1533033820986824
    1. Skórska M, Piotrowski T, Ryczkowski A, Kaźmierska J. Comparison of treatment planning parameters for dose painting head and neck plans delivered with tomotherapy. Br J Radiol. 2016;89(1060):20150970. doi:10.1259/bjr.20150970
    1. Shimizu H, Sasaki K, Tachibana H, et al. Analysis of modulation factor to shorten the delivery time in helical tomotherapy. J Appl Clin Med Phys. 2017;18(3):83-87. doi:10.1002/acm2.12075
    1. Van Gestel D, van Vliet-Vroegindeweij C, Van den Heuvel F. Rapidarc, SmartArc and TomoHD compared with classical step and shoot and sliding window intensity modulated radiotherapy in an oropharyngeal cancer treatment plan comparison. Radiat Oncol. 2013;8:37. doi:10.1186/1748-717X-8-37
    1. Van Gestel D, De Kerf G, Wouters K, et al. Fast helical tomotherapy in a head and neck cancer planning study: is time priceless? Radiat Oncol. 2015;10:261. doi:10.1186/s13014-015-0556-8
    1. Meyer P, Bouhours H, Dehaynin N, et al. The optimal tomotherapy treatment planning parameters for extremity soft tissue sarcomas. Phys Med. 2015;31(5):542-552. doi:10.1016/j.ejmp.2015.05.005
    1. Ryczkowski A, Piotrowski T. Influence of the modulation factor on the treatment plan quality and execution time in tomotherapy in head and neck cancer: in-phantom study. J Cancer Res Ther. 2013;9(4):618-623. doi:10.4103/0973-1482.126458
    1. De Kerf G, Van Gestel D, Mommaerts L, Van den Weyngaert D, Verellen D. Evaluation of the optimal combinations of modulation factor and pitch for helical tomotherapy plans made with tomoedge using pareto optimal fronts. Radiat Oncol. 2015;10(1):1-7. doi:10.1186/s13014-015-0497-2
    1. Krayenbuehl J, Di Martino M, Guckenberger M, Andratschke N. Improved plan quality with automated radiotherapy planning for whole brain with hippocampus sparing: a comparison to the RTOG 0933 trial. Radiat Oncol. 2017;12:161. doi:10.1186/s13014-017-0896-7
    1. Feng CH, Cornell M, Moore KL, Karunamuni R, Seibert TM. Automated contouring and planning pipeline for hippocampal-avoidant whole-brain radiotherapy. Radiat Oncol. 2020;15(1):251. doi:10.1186/s13014-020-01689-y
    1. Shimizu H, Sasaki K, Kubota T, et al. Interfacility variation in treatment planning parameters in tomotherapy: field width, pitch, and modulation factor. J Radiat Res. 2018;59(5):664-668. doi:10.1093/jrr/rry042
    1. Gondi V, Tolakanahalli R, Mehta MP, et al. Hippocampal-sparing whole-brain radiotherapy: a “how-to” technique using helical tomotherapy and linear accelerator-based intensity-modulated radiotherapy. Int J Radiat Oncol Biol Phys. 2010;78(4):1244-1252. doi:10.1016/j.ijrobp.2010.01.039
    1. 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(5):64-74. doi:10.1002/acm2.12581
    1. Gutiérrez AN, Westerly DC, Tomé WA, et al. Whole brain radiotherapy with hippocampal avoidance and simultaneously integrated brain metastases boost: a planning study. Int J Radiat Oncol Biol Phys. 2007;69(2):589-597. doi:10.1016/j.ijrobp.2007.05.038
    1. Moldovan M, Fontenot JD, Gibbons JP, et al. Investigation of pitch and jaw width to decrease delivery time of helical tomotherapy treatments for head and neck cancer. Med Dosim. 2011;36(4):397-403. doi:10.1016/j.meddos.2010.10.001
    1. Skórska M, Piotrowski T. Optimization of treatment planning parameters used in tomotherapy for prostate cancer patients. Phys Medica. 2013;29(3):273-285. doi:10.1016/j.ejmp.2012.03.007

Source: PubMed

Patrocinadores y Colaboradores

Condiciones médicas

Intervenciones de drogas

3
Suscribir