METHODS: A 48-year-old female with recurrent anaplastic meningioma, World Health Organization grade 3, underwent a right-sided craniotomy using off-label 5-ALA as a surgical adjunct. The patient had previously undergone brachytherapy seed implantation (20 × cesium 131) for tumor management. During the surgery, a large fluorescent tumor mass adjacent to the brachytherapy-treated area was resected, and the prior brachytherapy seeds were removed. Interestingly, the surrounding brain tissue in the irradiated area showed robust 5-ALA fluorescence. Pathological examination confirmed that the fluorescent brain tissue was nonneoplastic and associated with lymphocyte and macrophage infiltration.
CONCLUSIONS: This case report presents unique 5-ALA fluorescence in nonneoplastic tissue following brachytherapy, which was found during the resection of recurrent anaplastic meningioma. This phenomenon may reflect an intricate interplay among radiation therapy, immune cells, the tumor microenvironment, and 5-ALA metabolism. Given that false-positive findings in fluorescence-guided surgery can lead to unnecessary tissue resection and increased surgical morbidity, further research is warranted to elucidate the mechanisms underlying this phenomenon and its implications for meningioma surgery.
方法:一名48岁女性复发性间变性脑膜瘤,世界卫生组织3级,使用标签外5-ALA作为手术辅助手段进行了右侧开颅手术。该患者先前曾接受近距离放射治疗种子植入(20×铯131)进行肿瘤治疗。在手术过程中,切除了近距离放射治疗区域附近的一个大的荧光肿瘤块,并去除先前的近距离放射治疗种子。有趣的是,照射区域的周围脑组织显示出强烈的5-ALA荧光。病理检查证实荧光脑组织为非肿瘤性,并伴有淋巴细胞和巨噬细胞浸润。
结论:本病例报告显示近距离放射治疗后非肿瘤组织中独特的5-ALA荧光,这是在切除复发性间变性脑膜瘤时发现的。这种现象可能反映了放射治疗之间复杂的相互作用,免疫细胞,肿瘤微环境,和5-ALA代谢。鉴于荧光引导手术中的假阳性结果可能导致不必要的组织切除和增加手术发病率,需要进一步的研究来阐明这一现象的潜在机制及其对脑膜瘤手术的影响.