Nakamura Naoki, Hojo Hidehiro, Inoue Kazuya, Hotta Kenji, Zenda Sadamoto, Baba Hiromi, Onozawa Masakatsu, Motegi Atsushi, Nakamura Masaki, Kibe Yuichi, Akimoto Tetsuo
Division of Radiation Oncology and Particle Therapy, National Cancer Center Hospital East, 6-5-1 Kashiwanoha, Kashiwa, Chiba, Japan.
Department of Radiology, Takai Hospital, 470-8 Kuranosho, Tenri, Nara, Japan.
J Radiat Res. 2018 Jul 1;59(4):456-461. doi: 10.1093/jrr/rry028.
This study aimed to examine late radiological changes after proton beam therapy (PBT) for early-stage non-small cell lung cancer (NSCLC) and to clarify correlations between mass-like radiological changes and patient characteristics. CT scans of patients who underwent passive scattering PBT for T1-2N0M0 NSCLC were analyzed retrospectively. Patients were considered eligible if follow-up CT was performed for at least 2 years, with no definite evidence of local recurrence. The following five periods were defined: (i) 6-12 months, (ii) 12-24 months, (iii) 24-36 months, (iv) 36-48 months and (v) 48-60 months after PBT. Late (≥6 months) radiological changes were scored by consensus of three radiation oncologists according to classifications set forth by Koenig (Radiation injury of the lung after three-dimensional conformal radiation therapy. AJR Am J Roentgenol 2002;178:1383-8.). CT scans of 113 patients (median follow-up, 36 months; range, 24-137 months) were evaluated. Late radiological changes during Periods (i), (ii), (iii), (iv) and (v) included modified conventional pattern (80%, 79%, 72%, 58% and 56%, respectively), mass-like changes (8%, 9%, 14%, 22% and 18%, respectively), scar-like changes (4%, 9%, 11%, 17% and 24%, respectively) and no increased density (8%, 3%, 3%, 2% and 2%, respectively). Mass-like changes were observed in 23 patients (20%). Among patients who developed mass-like changes, the median interval between the initiation of PBT and the onset of mass-like changes was 19 months (range, 6-62 months). In multivariate analysis, a peripheral location was found to be a significant factor (P = 0.035; odds ratio: 4.44; 95% confidence interval: 1.12-21.28). In conclusion, mass-like changes were observed in 20% of patients who underwent PBT. Patients with peripheral tumors showed a higher incidence of mass-like changes.
本研究旨在探讨早期非小细胞肺癌（NSCLC）质子束治疗（PBT）后的晚期影像学变化，并阐明类似肿块的影像学变化与患者特征之间的相关性。对接受被动散射PBT治疗T1-2N0M0 NSCLC的患者的CT扫描进行回顾性分析。如果随访CT至少进行2年且无明确的局部复发证据，则认为患者符合条件。定义了以下五个时期：（i）PBT后6-12个月，（ii）12-24个月，（iii）24-36个月，（iv）36-48个月和（v）48-60个月。由三位放射肿瘤学家根据Koenig提出的分类标准（三维适形放射治疗后肺的放射损伤。AJR美国放射学杂志2002；178：1383-8）达成共识，对晚期（≥6个月）影像学变化进行评分。对113例患者（中位随访时间36个月；范围24-137个月）的CT扫描进行了评估。在时期（i）、（ii）、（iii）、（iv）和（v）的晚期影像学变化包括改良传统模式（分别为80%、79%、72%、58%和56%）、类似肿块的变化（分别为8%、9%、14%、22%和18%）、类似瘢痕的变化（分别为4%、9%、11%、17%和24%）以及密度无增加（分别为8%、3%、3%、2%和2%）。23例患者（20%）出现类似肿块的变化。在出现类似肿块变化的患者中，PBT开始至类似肿块变化出现的中位间隔时间为19个月（范围6-62个月）。多因素分析显示，周围型是一个显著因素（P = 0.035；优势比：4.44；95%置信区间：1.12-21.28）。总之，接受PBT的患者中有20%出现类似肿块的变化。周围型肿瘤患者出现类似肿块变化的发生率更高。
