Bluemke Emma, Bulte Daniel, Bertrand Ambre, George Ben, Cooke Rosie, Chu Kwun-Ye, Durrant Lisa, Goh Vicky, Jacobs Clare, Ng Stasya M, Strauss Victoria Y, Hawkins Maria A, Muirhead Rebecca
Institute of Biomedical Engineering, University of Oxford, UK.
Radiotherapy Department, Oxford University Hospitals NHS Foundation Trust, UK.
Clin Transl Radiat Oncol. 2020 Mar 18;22:44-49. doi: 10.1016/j.ctro.2020.03.001. eCollection 2020 May.
Oxygen-enhanced magnetic resonance imaging (MRI) and T1-mapping was used to explore its effectiveness as a prognostic imaging biomarker for chemoradiotherapy outcome in anal squamous cell carcinoma.
T2-weighted, T1 mapping, and oxygen-enhanced T1 maps were acquired before and after 8-10 fractions of chemoradiotherapy and examined whether the oxygen-enhanced MRI response relates to clinical outcome. Patient response to treatment was assessed 3 months following completion of chemoradiotherapy. A mean T1 was extracted from manually segmented tumour regions of interest and a paired two-tailed -test was used to compare changes across the patient population. Regions of subcutaneous fat and muscle tissue were examined as control ROIs.
There was a significant increase in T1 of the tumour ROIs across patients following the 8-10 fractions of chemoradiotherapy (paired -test, p < 0.001, n = 7). At baseline, prior to receiving chemoradiotherapy, there were no significant changes in T1 across patients from breathing oxygen (n = 9). In the post-chemoRT scans (8-10 fractions), there was a significant decrease in T1 of the tumour ROIs across patients when breathing 100% oxygen (paired -test, p < 0.001, n = 8). Out of the 12 patients from which we successfully acquired a visit 1 T1-map, only 1 patient did not respond to treatment, therefore, we cannot correlate these results with clinical outcome.
These clinical data demonstrate feasibility and potential for T1-mapping and oxygen enhanced T1-mapping to indicate perfusion or treatment response in tumours of this nature. These data show promise for future work with a larger cohort containing more non-responders, which would allow us to relate these measurements to clinical outcome.
采用氧增强磁共振成像（MRI）和T1映射技术，探讨其作为肛管鳞状细胞癌放化疗疗效的预后成像生物标志物的有效性。
在进行8 - 10次放化疗前后采集T2加权、T1映射和氧增强T1图谱，检查氧增强MRI反应是否与临床结果相关。放化疗结束3个月后评估患者的治疗反应。从手动分割的肿瘤感兴趣区域提取平均T1值，并采用配对双尾检验比较患者群体的变化。将皮下脂肪和肌肉组织区域作为对照感兴趣区域进行检查。
在进行8 - 10次放化疗后，患者肿瘤感兴趣区域的T1值显著增加（配对检验，p < 0.001，n = 7）。在接受放化疗前的基线期，吸氧患者的T1值在患者之间无显著变化（n = 9）。在放化疗后扫描（8 - 10次）中，当呼吸100%氧气时，患者肿瘤感兴趣区域的T1值显著降低（配对检验，p < 0.001，n = 8）。在我们成功获取第1次T1图谱的12例患者中，只有1例患者对治疗无反应，因此，我们无法将这些结果与临床结果相关联。
这些临床数据证明了T1映射和氧增强T1映射在指示此类肿瘤灌注或治疗反应方面的可行性和潜力。这些数据为未来对包含更多无反应者的更大队列进行研究带来了希望，这将使我们能够将这些测量结果与临床结果相关联。
