Xu Kali, Khine Kay T, Ooi Yinn Cher, Quinsey Carolyn S
University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States.
Department of Ophthalmology, Kittner Eye Center, University of North Carolina School of Medicine, Chapel Hill, North Carolina, United States; Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida, United States.
Clin Neurol Neurosurg. 2018 Nov;174:239-243. doi: 10.1016/j.clineuro.2018.09.038. Epub 2018 Sep 27.
Extraneural metastasis (ENM) of primary central nervous system (CNS) tumors is an uncommon occurrence. Case reports and case series describe ENM after shunting, but this phenomenon has not been well characterized. In this review we aim to better understand the risk factors and clinical implications of ENM associated with shunting. A literature search of cases of ENM related to shunt placement in patients with primary CNS tumors reported through January 2018 was performed using PubMed and Google Scholar. We identified 106 cases of ENM of primary CNS tumors related to shunt placement. The three most common tumor histologies resulting in ENM were germinoma (24%), medulloblastoma (21%), and glioblastoma (11%). Of the patients with ENM, 48% had leptomeningeal spread and 37% had brain or spinal cord metastasis. Mean survival time from shunt placement was 13 months. Ventriculoatrial-shunted cases had higher rates of widespread metastasis and shorter average survival time from shunt placement (2 months) than the average of all types of shunts. Given the known association with ENM, careful consideration should be given to shunt placement in patients with primary CNS tumors, especially germinomas, medulloblastomas, and glioblastomas. Appropriate surveillance should be instituted after shunt placement, and leptomeningeal or neural metastasis should prompt the consideration of potential ENM. When considering distal shunt options, our review suggests that ventriculoatrial shunts should be avoided if possible. For truly obstructive pathologies, the risk of ENM is a further indication to consider other treatment options such as endoscopic third ventriculostomy rather than shunt placement.
原发性中枢神经系统（CNS）肿瘤的神经外转移（ENM）并不常见。病例报告和病例系列描述了分流术后的ENM，但这种现象尚未得到充分的特征描述。在本综述中，我们旨在更好地了解与分流相关的ENM的危险因素和临床意义。使用PubMed和谷歌学术对截至2018年1月报道的原发性CNS肿瘤患者中与分流置入相关的ENM病例进行了文献检索。我们确定了106例与分流置入相关的原发性CNS肿瘤的ENM病例。导致ENM的三种最常见肿瘤组织学类型是生殖细胞瘤（24%）、髓母细胞瘤（21%）和胶质母细胞瘤（11%）。在发生ENM的患者中，48%有软脑膜播散，37%有脑或脊髓转移。从分流置入开始计算的平均生存时间为13个月。与所有类型分流的平均值相比，脑室心房分流病例的广泛转移率更高，从分流置入开始计算的平均生存时间更短（2个月）。鉴于已知与ENM有关联，对于原发性CNS肿瘤患者，尤其是生殖细胞瘤、髓母细胞瘤和胶质母细胞瘤患者，应谨慎考虑分流置入。分流置入后应进行适当的监测，软脑膜或神经转移应促使考虑潜在的ENM。在考虑远端分流选择时，我们的综述表明，应尽可能避免使用脑室心房分流。对于真正的梗阻性病变，ENM的风险是考虑其他治疗选择（如内镜下第三脑室造瘘术）而非分流置入的进一步指征。
