Feasibility of fast, four-dimensional computed tomography-based O-ring LINAC plans for lung stereotactic body radiotherapy in patients with poor performance status

Eun Jeong Heo; Minseok Kim; Chun Gun Park; Kyung Hwan Chang; Kwang Hyeon Kim; Jang Bo Shim; Young Je Park; Chul Yong Kim; Nam Kwon Lee; Suk Lee

doi:10.3389/fonc.2023.1270677

Feasibility of fast, four-dimensional computed tomography-based O-ring LINAC plans for lung stereotactic body radiotherapy in patients with poor performance status

Front Oncol. 2023 Nov 20:13:1270677. doi: 10.3389/fonc.2023.1270677. eCollection 2023.

Authors

Eun Jeong Heo^{1

2}, Minseok Kim³, Chun Gun Park⁴, Kyung Hwan Chang⁵, Kwang Hyeon Kim⁶, Jang Bo Shim⁷, Young Je Park¹, Chul Yong Kim¹, Nam Kwon Lee¹, Suk Lee¹

Affiliations

¹ Department of Radiation Oncology, College of Medicine, Korea University, Seoul, Republic of Korea.
² Department of Medical Physics, Graduate School of Korea University, Sejong, Republic of Korea.
³ Department of Biostatistics and Computing, Yonsei University Graduate School, Seoul, Republic of Korea.
⁴ Department of Mathematics, Kyonggi University, Suwon-si, Gyeonggi, Republic of Korea.
⁵ Department of Radiologic Science, Far East University, Eumseong-gun, Chungcheongbuk-do, Republic of Korea.
⁶ Department of Neurosurgery, Ilsan Paik Hospital, College of Medicine, Inje University, Goyang-si, Gyeonggi-do, Republic of Korea.
⁷ Department of Radiation Oncology, Guro Hospital, Korea University Medical Center, Seoul, Republic of Korea.

Abstract

Purpose: We aimed to retrospectively analyzed the feasibility of fast four-dimensional computed tomography (4DCT)-based O-ring LINAC treatment for patients with an average respiratory amplitude was< 0.5 cm and who cannot endure long treatment times due to poor performance status in lung 4D-stereotactic body radiotherapy (SBRT).

Methods: This study included data of 38 patients who received lung 4D-SBRT and had average respiratory amplitude< 0.5 cm in the full phase. C-arm LINAC plans were based on 4DCT data obtained at phase values ranging from 20-70% using a C-arm LINAC. O-ring LINAC plans were retrospectively established based on 4DCT data obtained at phase values of 0-90% using an O-ring LINAC. The conformity index (CI), homogeneity index (HI), and gradient measurement of the planning target volumes (PTV) were analyzed to compare dosimetric data between C-arm LINAC and O-ring LINAC plans. Organs at risk were analyzed in accordance with the Radiation Therapy Oncology Group 0915 protocol. Treatment delivery time and total monitor units were analyzed to compare the efficiency of treatment delivery. Statistical comparisons were performed using the Wilcoxon signed-rank test (P< 0.05).

Results: For the PTV, there was no significant difference in the CI or HI between C-arm LINAC and O-ring LINAC plans. For organs-at-risk, all plans met the criteria for dose constraint. There was a significant difference between C-arm LINAC and O-ring LINAC plans except in the spinal cord. Treatment delivery time was 92% longer for C-arm LINAC plans than for O-ring LINAC plans. The total MU value for C-arm LINAC plans was 9.6% higher than that for O-ring LINAC plans.

Conclusion: We verified the feasibility of fast 4DCT-based O-ring LINAC treatment for patients with average respiratory amplitude< 0.5 cm and who cannot endure long treatment times due to poor performance status in lung 4D-SBRT.

Keywords: 4D-SBRT; O-ring LINAC; fast treatment; lung cancer; poor performance status.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (N0. 2021R1G1A1003584) and Korea University (No. K1925071). The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication.