Ocaña-Tienda Beatriz, Pérez-Beteta Julián, Molina-García David, Asenjo Beatriz, Ortiz de Mendivil Ana, Albillo David, Pérez-Romasanta Luís A, González Del Portillo Elisabeth, Llorente Manuel, Carballo Natalia, Arana Estanislao, Pérez-García Víctor M
Mathematical Oncology Laboratory, University of Castilla-La Mancha, Ciudad Real, Spain.
Department of Radiology, Hospital Regional Universitario Carlos Haya, Málaga, Spain.
Neurooncol Adv. 2022 Dec 8;5(1):vdac179. doi: 10.1093/noajnl/vdac179. eCollection 2023 Jan-Dec.
Radiation necrosis (RN) is a frequent adverse event after fractionated stereotactic radiotherapy (FSRT) or single-session stereotactic radiosurgery (SRS) treatment of brain metastases (BMs). It is difficult to distinguish RN from progressive disease (PD) due to their similarities in the magnetic resonance images. Previous theoretical studies have hypothesized that RN could have faster, although transient, growth dynamics after FSRT/SRS, but no study has proven that hypothesis using patient data. Thus, we hypothesized that lesion size time dynamics obtained from growth laws fitted with data from sequential volumetric measurements on magnetic resonance images may help in discriminating recurrent BMs from RN events.
A total of 101 BMs from different institutions, growing after FSRT/SRS (60 PDs and 41 RNs) in 86 patients, displaying growth for at least 3 consecutive MRI follow-ups were selected for the study from a database of 1031 BMs. The 3 parameters of the Von Bertalanffy growth law were determined for each BM and used to discriminate statistically PDs from RNs.
Growth exponents in patients with RNs were found to be substantially larger than those of PD, due to the faster, although transient, dynamics of inflammatory processes. Statistically significant differences ( < .001) were found between both groups. The receiver operating characteristic curve (AUC = 0.76) supported the ability of the growth law exponent to classify the events.
Growth law exponents obtained from sequential longitudinal magnetic resonance images after FSRT/SRS can be used as a complementary tool in the differential diagnosis between RN and PD.
放射性坏死（RN）是脑转移瘤（BM）分次立体定向放射治疗（FSRT）或单次立体定向放射外科治疗（SRS）后常见的不良事件。由于磁共振图像上两者表现相似，因此很难将RN与疾病进展（PD）区分开来。以往的理论研究推测，RN在FSRT/SRS后可能具有更快（尽管是短暂的）生长动力学，但尚无研究使用患者数据证实这一假设。因此，我们推测，根据磁共振图像上连续体积测量数据拟合生长规律所获得的病变大小时间动态变化，可能有助于区分复发性BM和RN事件。
从1031例BM的数据库中，选取86例患者中在FSRT/SRS后生长的101例BM（60例PD和41例RN），这些BM在至少连续3次MRI随访中显示有生长，用于本研究。确定每个BM的冯·贝塔朗菲生长规律的3个参数，并用于从统计学上区分PD和RN。
由于炎症过程的动力学更快（尽管是短暂的），发现RN患者的生长指数显著大于PD患者。两组之间存在统计学显著差异（<0.001）。受试者工作特征曲线（AUC = 0.76）支持生长规律指数对事件进行分类的能力。
FSRT/SRS后从连续纵向磁共振图像获得的生长规律指数，可作为鉴别RN和PD的辅助工具。
