Taylor B Frazier, Knisely Jonathan P, Qian Jack M, Yu James B, Chiang Veronica L
Yale School of Medicine, Department of Therapeutic Radiology, 15 York Street, New Haven, CT 06510, USA.
Department of Radiation Medicine, North Shore-Long Island Jewish Health System and Hofstra-North Shore-LIJ School of Medicine, 300 Community Drive, Manhasset, NY 11030, USA.
J Radiosurg SBRT. 2016;4(1):53-60.
Treatment-related imaging changes (TRICs) after stereotactic radiosurgery (SRS) involves the benign transient enlargement of radiographic lesions after treatment. Identifying the radiation dose volumes and conformality metrics associated with TRICs for different post-treatment periods would be helpful and improve clinical decision making.
367 metastases in 113 patients were treated using Gamma Knife SRS between 1/1/2007-12/31/2009. Each metastasis was measured at each imaging follow-up to detect TRICs (defined as ≥ 20% increase in volume). Fluctuations in small volume lesions (less than 108 mm) were ignored given widely variable conformity indices (CI) for small volumes. The Karolinska Adverse Radiation Effect (KARE) factor, Paddick's CI, Shaw's CI, tumor volume (TV), 10 Gy (V10) and 12 Gy (V12) volumes, and prescription isodose volume (PIV) were calculated.
From 0-6 months, all measures correlated with the incidence of TRICs (p<.001), except KARE, which was inversely correlated. During the 6-12 month period all measures except KARE were still correlated. Beyond 12 months, no correlation was found between any of the measures and the development of TRICs.
All metrics except KARE were associated with TRICs from 0-12 months only. Additional patient and treatment factors may become dominant at greater times after SRS.
立体定向放射外科治疗（SRS）后与治疗相关的影像改变（TRICs）包括治疗后影像学病灶的良性短暂增大。确定不同治疗后时期与TRICs相关的辐射剂量体积和适形度指标将有助于改善临床决策。
2007年1月1日至2009年12月31日期间，使用伽玛刀SRS对113例患者的367处转移灶进行了治疗。每次影像随访时对每个转移灶进行测量，以检测TRICs（定义为体积增加≥20%）。鉴于小体积病灶（小于108立方毫米）的适形指数（CI）变化很大，忽略其波动。计算了卡罗林斯卡不良放射效应（KARE）因子、帕迪克CI、肖CI、肿瘤体积（TV）、10 Gy（V10）和12 Gy（V12）体积以及处方等剂量体积（PIV）。
在0至6个月期间，除KARE因子呈负相关外，所有测量指标均与TRICs的发生率相关（p<0.001）。在6至12个月期间，除KARE外的所有测量指标仍具有相关性。12个月后，未发现任何测量指标与TRICs的发生之间存在相关性。
除KARE外，所有指标仅在0至12个月期间与TRICs相关。在SRS后的更长时间，其他患者和治疗因素可能起主导作用。
