Anti-VEGF (vascular endothelial growth factor) treatment improves response rates, but not progression-free or overall survival in advanced breast cancer. It has been suggested that subgroups of patients may benefit from this treatment; however, the effects of adding anti-VEGF treatment to a standard chemotherapy regimen in breast cancer patients are not well studied. Understanding the effects of the anti-vascular treatment on tumor vasculature may provide a selection of patients that can benefit. The aim of this study was to study the vascular effect of bevacizumab using clinical dynamic contrast-enhanced MRI (DCE-MRI). A total of 70 women were randomized to receive either chemotherapy alone or chemotherapy with bevacizumab for 25 weeks. DCE-MRI was performed at baseline and at 12 and 25 weeks, and in addition 25 of 70 patients agreed to participate in an early MRI after one week. Voxel-wise pharmacokinetic analysis was performed using semi-quantitative methods and the extended Tofts model. Vascular architecture was assessed by calculating the fractal dimension of the contrast-enhanced images. Changes during treatment were compared with baseline and between the treatment groups. There was no significant difference in tumor volume at any point; however, DCE-MRI parameters revealed differences in vascular function and vessel architecture. Adding bevacizumab to chemotherapy led to a pronounced reduction in vascular DCE-MRI parameters, indicating decreased vascularity. At 12 and 25 weeks, the difference between the treatment groups is severely reduced.
抗血管内皮生长因子治疗可提高晚期乳腺癌的应答率，但未能改善无进展生存期或总生存期。有研究表明特定患者亚群可能从该治疗中获益，然而在乳腺癌患者标准化疗方案中联合抗血管内皮生长因子治疗的效果尚未得到充分研究。理解抗血管治疗对肿瘤脉管系统的影响可能有助于筛选潜在获益人群。本研究旨在通过临床动态对比增强磁共振成像技术探讨贝伐珠单抗的血管效应。共70例女性患者被随机分配接受单纯化疗或化疗联合贝伐珠单抗治疗25周。分别在基线期、第12周和第25周进行动态对比增强磁共振成像检查，其中70例患者中有25例同意在治疗1周后接受早期磁共振成像检查。采用半定量方法和扩展Tofts模型进行体素药代动力学分析，通过计算对比增强图像的分形维数评估血管结构。将治疗期间的变化与基线值及治疗组间进行比较。结果显示肿瘤体积在各时间点均无显著差异，但动态对比增强磁共振成像参数揭示了血管功能和血管结构的改变。化疗联合贝伐珠单抗治疗导致血管动态对比增强磁共振成像参数显著降低，提示血管生成减少。在第12周和第25周时，治疗组间的差异明显缩小。
肿瘤(癌症)患者之家