脳腫瘍患者のneuron specific enolase （NSE）値

THE VALUE OF NEURON SPECIFIC ENOLASE (NSE) IN THE PATIENTS OF BRAIN TUMORS

　抄録　神経細胞に特異的に分布すると考えられているneuron specific enolase （NSE）が診断や予後判定マーカーとして有用か否かを検討する目的で，頭蓋内腫瘍患者62例に対し，血清髄液および腫瘍内貯留液のNSE値をNSE RIA Kitによるradioimmunoassay 2抗体法を用いて測定した。正常成人血清中のNSE値は平均5.6±1.38ng／mlであったのに対し，low grade gliomaや間葉系腫瘍では有意の上昇は示さなかったがmalignant glioma患者血清では平均22.3±18.5ng／mlと高値を示し，未熟な外胚葉性腫瘍も平均16.1ng／mlと異常高値を示した。同一患者では血清よりも髄液中のNSE値が高い傾向を認め，腫瘍内貯留液は良性腫瘍においても異常高値を呈した。経時的観察において，血清NSE値の上昇は予後不良となる傾向がうかがわれ，腫瘍の増殖能，あるいは増殖に伴う組織の壊死の強さを反映している可能性が示唆された。radioimlnunoassay法によるNSEの測定は脳腫瘍の診断や予後判断の一助になりうると考えられる。

γ γ-Enolase is considered a specific protein of neuron, which is called neuron specific enolase (NSE). Recent reports clarified that NSE exists not only in neurons but also in neuroendocrine cells, thrombocytes and lymphocytes. Besides nor-mal neuronal tissues, high serum levels of NSE were noticed in the patients with neuroblastomas, small cell carcinomas of the lung, and malignant gliomas, etc. In order to clarify the usefulness of NSE as a marker for intracranial neoplasms or an indicator for prognosis of the patients with intra-cranial tumors, we studied serum, CSF and intra-tumoral fluid levels of NSE in 62 patients with intra-cranial tumors by radioimmunoassay. Serum level of NSE in healthy adults ranged from 4.1 to 8.9 ng/ml (5.6±1.38 ng/m/,n=15) and that of CSF ranged from 4.9 to 7.3 ng/ml (mean 6.1 ng/ml, n=3). Serum samples from patients with malig-nant gliomas and primitive neuroectodermal tu-mors contained abnormally high level of NSE, of which mean value were 22.3 ng/ml and 16.1 ng/ml, respectively.

However, serum samples from patients with low grade gliomas and other intracranial tumors ari-sing from non-neuroectodermal tissues were within normal range. In 9 patients, not only serum le-vels but CSF levels and/or intratumoral cyst levels of NSE were examined at the same time. Except one meningioma case, CSF levels of NSE were higher (4.9-55.3 ng/ml, mean : 19.3 ng/ml) than that of serum levels (2.3-17.3 ng/ml, mean : 12.7 ng/ml). Mean NSE concentrations of intratumoral fluids in both malignant and benign tumors were 181.7 ng/ml, respectively.

From the results of chronological examination of serum level of NSE in 6 patients with brain tumors, progressive elevation of the serum level of NSE revealed the poor prognosis. The chronolo-gical measurement of serum and/or CSF level of NSE by radioimmunoassay might help a judgement of the prognosis of the patients with intracranial tumors.