Treating early-stage centrally-located non-small cell lung cancer with DCAT-SBRT in centers lacking the VMAT technique: a comprehensive study

Yangyang Huang; Jun Yang; Rui Song; Tingting Qin; Menglin Yang; Yibao Liu

doi:10.3389/fonc.2024.1431082

Treating early-stage centrally-located non-small cell lung cancer with DCAT-SBRT in centers lacking the VMAT technique: a comprehensive study

Front Oncol. 2024 Dec 5:14:1431082. doi: 10.3389/fonc.2024.1431082. eCollection 2024.

Authors

Yangyang Huang^{1

2}, Jun Yang², Rui Song², Tingting Qin², Menglin Yang², Yibao Liu¹

Affiliations

¹ School of Nuclear Science and Engineering, East China University of Technology, Nanchang, Jiangxi, China.
² Department of Radiotherapy, the Second Affiliated Hospital of Zhengzhou University, Zhengzhou, Henan, China.

Abstract

Background: Volumetric-modulated arc therapy (VMAT) may have the highest overall performance for stereotactic body radiotherapy (SBRT) treatment of inoperable early-stage NSCLC. However, in centers lacking the VMAT technique, the dynamic conformal arc therapy (DCAT) technique is potentially the best option for small and rounded NSCLC-SBRT. Therefore, we will comprehensively analyze the advantages of the DCAT versus the other techniques except VMAT in terms of dosimetry, plan complexity, delivery time, γ-passing rates and the interplay effect.

Methods: 36 patients with early-stage centrally located NSCLC with PTV volumes < 65 cc were enrolled. All patients were redesigned with 50Gy/5f, and 100% of the prescribed dose was normalized to cover 95% of the PTV. The other two delivery techniques compared to the DCAT technique include 3-dimensional conformal radiotherapy (3DCRT) and intensity-modulated radiotherapy (IMRT), which use the same parameters for all three techniques.

Results: The dosimetric parameters of the 3-group plans all met the RTOG 0813 protocol. Unsurprisingly, plan complexity parameters such as segments and MUs were significantly reduced in the DCAT plans by 159.56 and 925.90 compared to the IMRT plans, respectively (all P < 0.001). The delivery time of the DCAT plans was the least of 164.51 s (all P < 0.05). Compared to the IMRT plans, the γ-passing rates were higher in the DCAT plans (P < 0.001), with the most significant difference of 6.01% in the (2%, 1 mm) criteria. As for the interplay effect, the mean dose difference (MDD) in the DCAT plans was as good as the 3DCRT plans at different respiratory amplitudes but better than the IMRT plans (all P < 0.05), and the MDD of DCAT plans did not exceed 3% in all respiratory amplitude.

Conclusion: In centers lacking the VMAT technique, implementing SBRT treatment based on the DCAT technique for inoperable early-stage centrally-located NSCLC patients with PTV volumes < 65 cc achieves better treatment efficiency and delivery accuracy while maintaining the plan quality.

Keywords: DCAT; SBRT; delivery time; dosimetric parameter; inoperable early-stage centrally-located NSCLC; interplay effect; plan complexity; γ-passing rate.

Grants and funding

The author(s) declare financial support was received for the research, authorship, and/or publication of this article. Research reported in this publication was supported by the Henan Science and Technology under award number 232102310091, Henan Medical Science and Technology Foundation under award number LHGJ20210407, and National Natural Science Foundation of China under award number 11965001.