Department of Medical Oncology, Dr. B. R. A. Institute Rotary Cancer Hospital, All India Institute of Medical Sciences, New Delhi, India.
Pediatr Blood Cancer. 2010 Apr;54(4):526-31. doi: 10.1002/pbc.22328.
Measurement of tumor angiogenesis by qualitative analysis of dynamic contrast enhanced-magnetic resonance imaging (DCE-MRI), and its association with diffusion-weighted (DW)-MRI and glucose metabolism using positron emission tomography-computerized tomography (PET-CT) scan has not been explored in osteosarcoma. Present study was aimed to evaluate the potential of these surrogates.
Thirty-one treatment naive patients with osteosarcoma underwent MRI and PET-CT preceding and following three cycles of neoadjuvant chemotherapy (NACT) and surgery. Time intensity curves (TICs) representing low microvascular permeability is persistent type while that of high permeability are plateau and washout types. Vascular endothelial growth factor (VEGF) expression was assessed in biopsy and resected specimens by immunohistochemistry. The sample was considered VEGF positive when intensive positive staining of VEGF was observed in >10% of the tumor cells in biopsy or resection specimens.
TIC could correctly identify all 28 VEGF positive samples at baseline and 24/25 (96%) of VEGF positive samples and 5/6 (83%) of VEGF negative samples after NACT. The change in curve pattern from washout/plateau to persistent type was in agreement with corresponding decrease in microvascular permeability, that is, VEGF expression. For persistent type of TIC, mean change in VEGF was 73.3 +/- 43.2% and for plateau and washout type of TIC it was 19.54 +/- 45% and 16.66 +/- 28.86%, respectively (P <or= 0.04). VEGF expression did not correlate with DW-MRI and PET-CT parameters.
This study suggests an important role of DCE-MRI as a noninvasive imaging surrogate of tumor angiogenesis in osteosarcoma based on visual inspection of TIC.
通过动态对比增强磁共振成像（DCE-MRI）的定性分析来测量肿瘤血管生成，并结合使用正电子发射断层扫描-计算机断层扫描（PET-CT）扫描的扩散加权（DW）-MRI 和葡萄糖代谢来评估其在骨肉瘤中的应用。本研究旨在评估这些替代物的潜力。
31 例未经治疗的骨肉瘤患者在新辅助化疗（NACT）前和后进行 MRI 和 PET-CT 检查，并进行了 3 个周期的治疗和手术。TIC 曲线（TICs）代表低微血管通透性为持续型，高通透性为平台型和洗脱型。通过免疫组织化学评估活检和切除标本中的血管内皮生长因子（VEGF）表达。在活检或切除标本中，如果观察到 >10%的肿瘤细胞有密集的 VEGF 阳性染色，则认为样本为 VEGF 阳性。
TIC 可以在基线时正确识别所有 28 例 VEGF 阳性样本，在 NACT 后可以正确识别 24/25（96%）例 VEGF 阳性样本和 5/6（83%）例 VEGF 阴性样本。曲线类型从洗脱/平台型转变为持续型与微血管通透性的相应降低一致，即 VEGF 表达。对于 TIC 的持续型，VEGF 的平均变化为 73.3% ± 43.2%，而对于 TIC 的平台型和洗脱型，VEGF 的平均变化分别为 19.54% ± 45%和 16.66% ± 28.86%（P <0.04）。VEGF 表达与 DW-MRI 和 PET-CT 参数不相关。
这项研究表明，DCE-MRI 在骨肉瘤中作为肿瘤血管生成的非侵入性成像替代物具有重要作用，其依据是 TIC 的直观检查。
