Department of Radiation Oncology, University of Michigan Medical Center, 1500 E. Medical Center Dr, Ann Arbor, MI 48109, USA.
J Clin Oncol. 2010 May 1;28(13):2293-9. doi: 10.1200/JCO.2009.25.3971. Epub 2010 Apr 5.
To assess whether a new method of quantifying therapy-associated hemodynamic alterations may help to distinguish pseudoprogression from true progression in patients with high-grade glioma.
Patients with high-grade glioma received concurrent chemoradiotherapy. Relative cerebral blood volume (rCBV) and blood flow (rCBF) maps were acquired before chemoradiotherapy and at week 3 during treatment on a prospective institutional review board-approved study. Pseudoprogression was defined as imaging changes 1 to 3 months after chemoradiotherapy that mimic tumor progression but stabilized or improved without change in treatment or for which resection revealed radiation effects only. Clinical and conventional magnetic resonance (MR) parameters, including average percent change of rCBV and CBF, were evaluated as potential predictors of pseudoprogression. Parametric response map (PRM), an innovative, voxel-by-voxel method of image analysis, was also performed.
Median radiation dose was 72 Gy (range, 60 to 78 Gy). Of 27 patients, stable disease/partial response was noted in 13 patients and apparent progression was noted in 14 patients. Adjuvant temozolomide was continued in all patients. Pseudoprogression occurred in six patients. Based on PRM analysis, a significantly reduced blood volume (PRM(rCBV)) at week 3 was noted in patients with progressive disease as compared with those with pseudoprogression (P < .01). In contrast, change in average percent rCBV or rCBF, MR tumor volume changes, age, extent of resection, and Radiation Therapy Oncology Group recursive partitioning analysis classification did not distinguish progression from pseudoprogression.
PRM(rCBV) at week 3 during chemoradiotherapy is a potential early imaging biomarker of response that may be helpful in distinguishing pseudoprogression from true progression in patients with high-grade glioma.
评估一种新的量化治疗相关血流动力学改变的方法是否有助于区分高级别脑胶质瘤患者的假性进展与真性进展。
高级别脑胶质瘤患者接受同期放化疗。在一项前瞻性机构审查委员会批准的研究中，患者在放化疗前和治疗第 3 周接受相对脑血容量（rCBV）和脑血流（rCBF）图。假性进展定义为放化疗后 1 至 3 个月出现的影像学改变，其模仿肿瘤进展，但无需改变治疗即可稳定或改善，或切除后仅显示放射效应。评估了临床和常规磁共振（MR）参数，包括 rCBV 和 CBF 的平均百分比变化，作为假性进展的潜在预测指标。还进行了参数反应图（PRM），这是一种创新的、基于体素的图像分析方法。
中位放疗剂量为 72 Gy（范围，60 至 78 Gy）。27 例患者中，13 例为稳定疾病/部分缓解，14 例为明显进展。所有患者均继续接受辅助替莫唑胺治疗。6 例患者出现假性进展。基于 PRM 分析，与假性进展患者相比，进展患者在第 3 周时的血容量明显减少（PRM（rCBV））（P<.01）。相比之下，平均 rCBV 或 rCBF 的变化百分比、MR 肿瘤体积变化、年龄、切除范围和放射治疗肿瘤组递归分区分析分类均不能区分进展与假性进展。
放化疗第 3 周时的 PRM（rCBV）是一种潜在的早期反应影像学生物标志物，可能有助于区分高级别脑胶质瘤患者的假性进展与真性进展。
