Plan quality comparison between 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy for the treatment of multiple brain metastases

Kotaro Yoshio, Toshiharu Mitsuhashi, Akihisa Wakita, Takahiro Kitayama, Kento Hisazumi, Daisaku Inoue, Tsuyoki Shiode, Shiro Akaki, Susumu Kanazawa

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

To compare the plans of 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy (VMA-SRT) for multiple brain metastases and to investigate the cutoff value for the tumor number and volume for 6-arc rather than 4-arc VMA-SRT. We identified 24 consecutive multiple-target cases (3 to 19 targets in each case) with 189 total targets. We constructed plans using both 4- and 6-arc noncoplanar VMA-SRT. The prescribed dose was 36 Gy/6 fr, and it was delivered to 95% of the planning target volume (PTV). The plans were evaluated for the dose conformity using the Radiation Therapy Oncology Group and Paddick conformity indices (RCI and PCI), fall-off (Paddick gradient index [PGI]), and the normal brain dose. The median (range) RCI, PCI, and PGI was 0.94 (0.92 to 0.99), 0.89 (0.77 to 0.94), and 3.75 (2.24 to 6.54) for the 4-arc plan and 0.94 (0.91 to 0.98), 0.89 (0.76 to 0.94), and 3.65 (2.24 to 6.5) for the 6-arc plan, respectively. The median (range) of the normal brain dose was 910.3 cGy (381.4 to 1268.9) for the 4-arc plan and 898.8 cGy (377 to 1252.9) for the 6-arc plan. The PGI of the 6-arc plan was significantly superior to that of the 4-arc plan (p = 0.0076), and the optimal cutoff values for the tumor number and volume indicative of 6-arc (and not 4-arc) VMA-SRT were cases with ≥ 5 metastases and a PTV of ≥ 12.9 mL, respectively. The PCI values, however, showed no significant difference between the 2 plans. We believe these results will help in considering the use of 6-arc VMA-SRT for multiple brain metastases.

Original languageEnglish
JournalMedical Dosimetry
DOIs
Publication statusAccepted/In press - Jan 1 2018

Fingerprint

Radiotherapy
Neoplasm Metastasis
Brain
Tumor Burden
Therapeutics
Radiation Oncology
Reference Values

Keywords

  • Brain metastases
  • Noncoplanar arc
  • Stereotactic radiotherapy
  • Volumetric modulated arc therapy

ASJC Scopus subject areas

  • Radiological and Ultrasound Technology
  • Oncology
  • Radiology Nuclear Medicine and imaging

Cite this

Plan quality comparison between 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy for the treatment of multiple brain metastases. / Yoshio, Kotaro; Mitsuhashi, Toshiharu; Wakita, Akihisa; Kitayama, Takahiro; Hisazumi, Kento; Inoue, Daisaku; Shiode, Tsuyoki; Akaki, Shiro; Kanazawa, Susumu.

In: Medical Dosimetry, 01.01.2018.

Research output: Contribution to journalArticle

@article{959f3cc144e847f0ad0bdf6505a6ab94,
title = "Plan quality comparison between 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy for the treatment of multiple brain metastases",
abstract = "To compare the plans of 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy (VMA-SRT) for multiple brain metastases and to investigate the cutoff value for the tumor number and volume for 6-arc rather than 4-arc VMA-SRT. We identified 24 consecutive multiple-target cases (3 to 19 targets in each case) with 189 total targets. We constructed plans using both 4- and 6-arc noncoplanar VMA-SRT. The prescribed dose was 36 Gy/6 fr, and it was delivered to 95{\%} of the planning target volume (PTV). The plans were evaluated for the dose conformity using the Radiation Therapy Oncology Group and Paddick conformity indices (RCI and PCI), fall-off (Paddick gradient index [PGI]), and the normal brain dose. The median (range) RCI, PCI, and PGI was 0.94 (0.92 to 0.99), 0.89 (0.77 to 0.94), and 3.75 (2.24 to 6.54) for the 4-arc plan and 0.94 (0.91 to 0.98), 0.89 (0.76 to 0.94), and 3.65 (2.24 to 6.5) for the 6-arc plan, respectively. The median (range) of the normal brain dose was 910.3 cGy (381.4 to 1268.9) for the 4-arc plan and 898.8 cGy (377 to 1252.9) for the 6-arc plan. The PGI of the 6-arc plan was significantly superior to that of the 4-arc plan (p = 0.0076), and the optimal cutoff values for the tumor number and volume indicative of 6-arc (and not 4-arc) VMA-SRT were cases with ≥ 5 metastases and a PTV of ≥ 12.9 mL, respectively. The PCI values, however, showed no significant difference between the 2 plans. We believe these results will help in considering the use of 6-arc VMA-SRT for multiple brain metastases.",
keywords = "Brain metastases, Noncoplanar arc, Stereotactic radiotherapy, Volumetric modulated arc therapy",
author = "Kotaro Yoshio and Toshiharu Mitsuhashi and Akihisa Wakita and Takahiro Kitayama and Kento Hisazumi and Daisaku Inoue and Tsuyoki Shiode and Shiro Akaki and Susumu Kanazawa",
year = "2018",
month = "1",
day = "1",
doi = "10.1016/j.meddos.2017.11.007",
language = "English",
journal = "Medical Dosimetry",
issn = "0958-3947",
publisher = "Elsevier Inc.",

}

TY - JOUR

T1 - Plan quality comparison between 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy for the treatment of multiple brain metastases

AU - Yoshio, Kotaro

AU - Mitsuhashi, Toshiharu

AU - Wakita, Akihisa

AU - Kitayama, Takahiro

AU - Hisazumi, Kento

AU - Inoue, Daisaku

AU - Shiode, Tsuyoki

AU - Akaki, Shiro

AU - Kanazawa, Susumu

PY - 2018/1/1

Y1 - 2018/1/1

N2 - To compare the plans of 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy (VMA-SRT) for multiple brain metastases and to investigate the cutoff value for the tumor number and volume for 6-arc rather than 4-arc VMA-SRT. We identified 24 consecutive multiple-target cases (3 to 19 targets in each case) with 189 total targets. We constructed plans using both 4- and 6-arc noncoplanar VMA-SRT. The prescribed dose was 36 Gy/6 fr, and it was delivered to 95% of the planning target volume (PTV). The plans were evaluated for the dose conformity using the Radiation Therapy Oncology Group and Paddick conformity indices (RCI and PCI), fall-off (Paddick gradient index [PGI]), and the normal brain dose. The median (range) RCI, PCI, and PGI was 0.94 (0.92 to 0.99), 0.89 (0.77 to 0.94), and 3.75 (2.24 to 6.54) for the 4-arc plan and 0.94 (0.91 to 0.98), 0.89 (0.76 to 0.94), and 3.65 (2.24 to 6.5) for the 6-arc plan, respectively. The median (range) of the normal brain dose was 910.3 cGy (381.4 to 1268.9) for the 4-arc plan and 898.8 cGy (377 to 1252.9) for the 6-arc plan. The PGI of the 6-arc plan was significantly superior to that of the 4-arc plan (p = 0.0076), and the optimal cutoff values for the tumor number and volume indicative of 6-arc (and not 4-arc) VMA-SRT were cases with ≥ 5 metastases and a PTV of ≥ 12.9 mL, respectively. The PCI values, however, showed no significant difference between the 2 plans. We believe these results will help in considering the use of 6-arc VMA-SRT for multiple brain metastases.

AB - To compare the plans of 4-arc and 6-arc noncoplanar volumetric modulated arc stereotactic radiotherapy (VMA-SRT) for multiple brain metastases and to investigate the cutoff value for the tumor number and volume for 6-arc rather than 4-arc VMA-SRT. We identified 24 consecutive multiple-target cases (3 to 19 targets in each case) with 189 total targets. We constructed plans using both 4- and 6-arc noncoplanar VMA-SRT. The prescribed dose was 36 Gy/6 fr, and it was delivered to 95% of the planning target volume (PTV). The plans were evaluated for the dose conformity using the Radiation Therapy Oncology Group and Paddick conformity indices (RCI and PCI), fall-off (Paddick gradient index [PGI]), and the normal brain dose. The median (range) RCI, PCI, and PGI was 0.94 (0.92 to 0.99), 0.89 (0.77 to 0.94), and 3.75 (2.24 to 6.54) for the 4-arc plan and 0.94 (0.91 to 0.98), 0.89 (0.76 to 0.94), and 3.65 (2.24 to 6.5) for the 6-arc plan, respectively. The median (range) of the normal brain dose was 910.3 cGy (381.4 to 1268.9) for the 4-arc plan and 898.8 cGy (377 to 1252.9) for the 6-arc plan. The PGI of the 6-arc plan was significantly superior to that of the 4-arc plan (p = 0.0076), and the optimal cutoff values for the tumor number and volume indicative of 6-arc (and not 4-arc) VMA-SRT were cases with ≥ 5 metastases and a PTV of ≥ 12.9 mL, respectively. The PCI values, however, showed no significant difference between the 2 plans. We believe these results will help in considering the use of 6-arc VMA-SRT for multiple brain metastases.

KW - Brain metastases

KW - Noncoplanar arc

KW - Stereotactic radiotherapy

KW - Volumetric modulated arc therapy

UR - http://www.scopus.com/inward/record.url?scp=85039918526&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85039918526&partnerID=8YFLogxK

U2 - 10.1016/j.meddos.2017.11.007

DO - 10.1016/j.meddos.2017.11.007

M3 - Article

JO - Medical Dosimetry

JF - Medical Dosimetry

SN - 0958-3947

ER -