Department of Radiology, Tokyo Medical University Hospital, Shinjuku, Japan.
Ann Med. 2021 Dec;53(1):267-273. doi: 10.1080/07853890.2020.1869297.
This study evaluated the correlation between radiation-induced lung injury (RILI) and dosimetric parameters on computed tomography (CT) images of stage I non-small cell lung cancer (NSCLC) patients undergoing intensity-modulated radiotherapy (IMRT).
Sixty-three stage I NSLC patients who underwent IMRT were enrolled in the study. The patients underwent CT within 6 months (acute phase) and 1.5 years (late phase) after radiotherapy. These were fused with the planned irradiation CT. The range of RILI was measured from 10% to 100%, with an IC in 10% increments.
The median interval from completion of radiotherapy to acute and late phase CT was 92 and 440 days, respectively. The median RILI ranges of the acute and late phases were in the 80% (20-100%) and 70% dose regions (20-100%), respectively. The significantly narrower range of RILI when lung V20 in the acute phase was less than 19.2% and that of V5 in the late phase was less than 27.6% at the time of treatment planning.
This study showed that RILI occurred in a localized range in stage I NSCLC patients who underwent IMRT. The range of RILI was correlated with V20 in the acute phase and V5 in the late phase. KEY MESSAGES RILI correlated with V20 in acute and V5 in late phase. The shadow of RILI occurred in 80% dose region in acute and 70% in late phase. No relationship exists between radiographic changes in RILI and PTV volume.
本研究评估了接受调强放疗（IMRT）的 I 期非小细胞肺癌（NSCLC）患者 CT 图像上的放射性肺损伤（RILI）与剂量学参数之间的相关性。
本研究纳入了 63 例接受 IMRT 的 I 期 NSCLC 患者。患者在放疗后 6 个月（急性期）和 1.5 年（晚期）进行 CT 检查。这些 CT 与计划照射 CT 融合。RILI 范围从 10%到 100%测量，以 10%的增量计算 IC。
从放疗结束到急性期和晚期 CT 的中位间隔时间分别为 92 天和 440 天。急性期和晚期 RILI 范围的中位数分别为 80%（20-100%）和 70%剂量区域（20-100%）。在治疗计划时，急性期肺 V20 小于 19.2%，晚期 V5 小于 27.6%时，RILI 的范围明显更窄。
本研究表明，接受 IMRT 的 I 期 NSCLC 患者的 RILI 发生在局部范围内。RILI 的范围与急性期的 V20 和晚期的 V5 相关。急性期 RILI 的阴影出现在 80%剂量区域，晚期为 70%。RILI 的放射性变化与 PTV 体积之间没有关系。
