Pôle de Pathologie Thoracique, Hôpitaux Universitaires, Université de Strasbourg, Faculté de Médecine, Strasbourg, France.
Respiration. 2013;86(2):100-8. doi: 10.1159/000342371. Epub 2012 Nov 13.
The development of three-dimensional conformal radiotherapy (3D-RT) has enabled the restriction of the dose to normal lung, limiting radiation-induced lung injury.
This study was designed to describe the time course of lung function until 7.5 months after 3D-RT in patients with lung cancer, and assess the relationship between lung function changes and dose-volume histogram (DVH) analysis or computed tomography scan changes. Radiation doses were optimized according to recent guidelines.
Sixty-five lung cancer patients treated with 3D-RT agreed to participate in this prospective, hospital-based study. Lung volumes, forced expiratory volume in 1 s (FEV1) and diffusing capacity of the lung for carbon monoxide (DLCO) were measured before radiotherapy (RT), 10 weeks, 4 and 7.5 months after the beginning of 3D-RT.
Eleven lung cancer patients (17%) developed grade 2-3 respiratory symptoms after RT. At 7.5 months, vital capacity (VC) was 96 ± 2%, total lung capacity (TLC) 95 ± 2%, FEV1 93 ± 2% and DLCO 90 ± 2% of the initial value. Only 15% of patients showed pulmonary function reduction > 20%. Patients with FEV1 or DLCO < 60% before RT did not show significant changes after RT. There were weak correlations between reduction of VC, TLC, FEV1 or DLCO and radiation dosimetric parameters and between reduction of VC or FEV1 and radiation-induced pneumonitis images.
In lung cancer, the reduction of lung function within 7.5 months after 3D-RT was small and correlated, albeit weakly, with DVH parameters. Patients with initially impaired lung function showed tiny changes in spirometry and DLCO values.
三维适形放疗（3D-RT）的发展使正常肺组织的剂量限制成为可能，从而限制了放射性肺损伤。
本研究旨在描述肺癌患者在接受 3D-RT 后 7.5 个月内的肺功能变化过程，并评估肺功能变化与剂量体积直方图（DVH）分析或计算机断层扫描（CT）变化之间的关系。根据最新指南优化了放射剂量。
65 名接受 3D-RT 的肺癌患者同意参与这项前瞻性、基于医院的研究。在放疗（RT）前、第 10 周、第 4 个月和第 7.5 个月时测量了肺容积、第 1 秒用力呼气量（FEV1）和一氧化碳弥散量（DLCO）。
11 名（17%）肺癌患者在 RT 后出现 2-3 级呼吸系统症状。在 7.5 个月时，肺活量（VC）为初始值的 96 ± 2%，肺总量（TLC）为 95 ± 2%，FEV1 为 93 ± 2%，DLCO 为 90 ± 2%。仅有 15%的患者出现肺功能下降>20%。在 RT 前 FEV1 或 DLCO<60%的患者在 RT 后没有明显变化。VC、TLC、FEV1 或 DLCO 的减少与放射剂量学参数之间存在弱相关，以及 VC 或 FEV1 的减少与放射诱导的肺炎图像之间存在弱相关。
在肺癌中，3D-RT 后 7.5 个月内肺功能的下降较小，与 DVH 参数相关，但相关性较弱。初始肺功能受损的患者在肺活量和 DLCO 值方面变化很小。
