Hong Angela M, Suo Chao, Valenzuela Michael, Haydu Lauren E, Jacobsen Kari D, Reisse Claudius H, Fogarty Gerald
Melanoma Institute Australia, Poche Centre, North Sydney, Australia; Department of Medicine, Central Clinical School, The University of Sydney, Australia; Department of Radiation Oncology, Royal Prince Alfred Hospital, Sydney, Australia; Australia and New Zealand Melanoma Trials Group, North Sydney, Australia.
Regenerative Neuroscience Group, Brain & Mind Research Institute, The University of Sydney, Australia.
Radiother Oncol. 2014 Apr;111(1):59-62. doi: 10.1016/j.radonc.2014.01.012. Epub 2014 Feb 20.
ANZMTG 01.07 WBRTMel is a phase 3 randomized trial to address the role of whole brain radiation therapy (WBRT) after local treatment of 1-3 melanoma brain metastases. Modern radiation therapy technologies can now conformally spare the hippocampus during WBRT and therefore potentially reduce the risk of neurocognitive deficit. The aims of this study were to report the prevalence of melanoma metastases within the hippocampal sparing region and to identify variables that correlate with the presence of metastases within the hippocampal sparing region.
The pre-local treatment MRI scans of 77 eligible WBRTMel patients were used to contour the individual metastasis and the hippocampus. The volume, location and closest distance of each metastasis to the hippocampus were recorded. Binary logistic regression was performed to assess the influence of factors on the location of a metastasis within 5mm of the hippocampus.
The median age was 61 and 66% were male. The distribution of the 115 metastases was frontal (50, 43.5%), parietal (23, 20.0%), temporal (13, 11.2%), occipital (18, 15.7%), cerebellum (10, 8.6%) and pineal gland (1, 1.0%). The median aggregate volume of the metastasis was 3516mm(3). None of the metastases were within the hippocampus. Four patients (5.2%) had metastases within 5mm of the hippocampus. The median distance from metastasis to the nearest hippocampus was 37.2mm. Only the total volume of metastases was a significant predictor for the risk of a metastasis within the hippocampal sparing region (OR 1.071, 95% CI: 1.003-1.144, p=0.040).
This study confirmed a low incidence of melanoma metastasis in the hippocampal sparing region at diagnosis. Given the lack of randomized data on the safety and benefit of hippocampal sparing WBRT, the current WBRTMel trial provides the opportunity to explore the feasibility of this technique.
ANZMTG 01.07 WBRTMel是一项3期随机试验，旨在探讨在局部治疗1 - 3个黑色素瘤脑转移瘤后全脑放射治疗（WBRT）的作用。现代放射治疗技术现在可以在WBRT期间保形性地避开海马体，因此有可能降低神经认知缺陷的风险。本研究的目的是报告海马体保留区域内黑色素瘤转移的发生率，并确定与海马体保留区域内转移灶存在相关的变量。
对77例符合条件的WBRTMel患者的局部治疗前MRI扫描进行分析，勾勒出各个转移瘤和海马体的轮廓。记录每个转移瘤的体积、位置以及与海马体的最近距离。采用二元逻辑回归分析评估各因素对距离海马体5mm以内转移瘤位置的影响。
中位年龄为61岁，男性占66%。115个转移瘤的分布情况为：额叶（50个，43.5%）、顶叶（23个，20.0%）、颞叶（13个，11.2%）、枕叶（18个，15.7%）、小脑（10个，8.6%）和松果体（1个，1.0%）。转移瘤的中位总体积为3516mm³。没有转移瘤位于海马体内。4例患者（5.2%）的转移瘤位于距离海马体5mm以内。转移瘤到最近海马体的中位距离为37.2mm。只有转移瘤的总体积是海马体保留区域内转移风险的显著预测因素（比值比1.071，95%可信区间：1.003 - 1.144，p = 0.040）。
本研究证实诊断时海马体保留区域内黑色素瘤转移的发生率较低。鉴于缺乏关于保留海马体的WBRT安全性和益处的随机数据，当前的WBRTMel试验为探索该技术的可行性提供了机会。
