Jang Jeong Yun, Kim Su Ssan, Song Si Yeol, Kim Yeon Joo, Kim Sung-Woo, Choi Eun Kyung
Department of Radiation Oncology, Asan Medical Center, University of Ulsan College of Medicine, 88 Olympic-ro 43-gil, Songpa-gu, Seoul, 05505, Republic of Korea.
Department of Radiation Oncology, Asan Medical Center, Seoul, Republic of Korea.
Radiat Oncol. 2021 Dec 4;16(1):231. doi: 10.1186/s13014-021-01930-2.
Immunotherapy has been administered to many patients with non-small-cell lung cancer (NSCLC). However, only few studies have examined toxicity in patients receiving an immune checkpoint inhibitor (ICI) after concurrent chemoradiotherapy (CCRT). Therefore, we performed a retrospective study to determine factors that predict radiation pneumonitis (RP) in these patients.
We evaluated the size of the planning target volume, mean lung dose (MLD), and the lung volume receiving more than a threshold radiation dose (VD) in 106 patients. The primary endpoint was RP ≥ grade 2, and toxicity was evaluated.
After CCRT, 51/106 patients were treated with ICI. The median follow-up period was 11.5 months (range, 3.0-28.2), and RP ≥ grade 2 occurred in 47 (44.3%) patients: 27 and 20 in the ICI and non-ICI groups, respectively. Among the clinical factors, only the use of ICI was associated with RP (p = 0.043). Four dosimetric variables (MLD, V20, V30, and V40) had prognostic significance in univariate analysis for occurrence of pneumonitis (hazard ratio, p-value; MLD: 2.3, 0.009; V20: 2.9, 0.007; V30: 2.3, 0.004; V40: 2.5, 0.001). Only V20 was a significant risk factor in the non-ICI group, and MLD, V30, and V40 were significant risk factors in the ICI group. The survival and local control rates were superior in the ICI group than in the non-ICI group, but no significance was observed.
Patients receiving ICI after definitive CCRT were more likely to develop RP, which may be related to the lung volume receiving high-dose radiation. Therefore, several factors should be carefully considered for patients with NSCLC.
免疫疗法已应用于许多非小细胞肺癌（NSCLC）患者。然而，仅有少数研究探讨了同步放化疗（CCRT）后接受免疫检查点抑制剂（ICI）治疗的患者的毒性反应。因此，我们开展了一项回顾性研究，以确定这些患者发生放射性肺炎（RP）的预测因素。
我们评估了106例患者的计划靶体积大小、平均肺剂量（MLD）以及接受超过阈值辐射剂量的肺体积（VD）。主要终点为RP≥2级，并对毒性反应进行评估。
CCRT后，106例患者中有51例接受了ICI治疗。中位随访期为11.5个月（范围3.0 - 28.2个月），47例（44.3%）患者发生RP≥2级：ICI组和非ICI组分别为27例和20例。在临床因素中，仅ICI的使用与RP相关（p = 0.043）。四个剂量学变量（MLD、V20、V30和V40）在放射性肺炎发生的单因素分析中具有预后意义（风险比，p值；MLD：2.3，0.009；V20：2.9，0.007；V30：2.3，0.004；V40：2.5，0.001）。在非ICI组中，仅V20是显著的危险因素，而在ICI组中，MLD、V30和V40是显著的危险因素。ICI组生存和局部控制率优于非ICI组，但差异无统计学意义。
根治性CCRT后接受ICI治疗的患者更易发生RP，这可能与接受高剂量辐射的肺体积有关。因此，对于NSCLC患者应仔细考虑多个因素。
