Abstract:

Abstract：Although the pathological diagnosis in combination with tumor markers has become a diagnostic norm of intracranial germ cell tumors(ICGCTs)，the existent concept “secreting germ cell tumors” and three empirical and “highly specific” diagnostic criteria(both cerebrospinal fluid /serum，β-hCG≥50 U/L/αFP≥10 μg/L；β-hCG≥100U/L/αFP≥50 μg/L；β-hCG>50 U/L/αFP>25 μg/L) are not realistic.In order to further investigate the two tumor markers’ diagnostical value，the paper first founds a multiple-disciplinary diagnostic platform in Peking Union Medical Hospital(PUMCH)，then after a thorough analysis of the valid data from the ICGCTs patients(n=58) within recent 31 years(1991.3-2012.12)，the paper put forwards some further propositions: clarifird the realative rationality of the existing criteria(β-hCG>50 U/L/αFP>25 μg/L)；after compares with the data of controlled suspicious ICGCTs patients (n=17) and calculated with receiver operating characteristic(ROC) curve，a newβ-hCG diagnostic cut-off point was confrimed: CSF β-hCG ≥8.4 U/L and serum β-hCG ≥2.2 U/L ( diagnostic sensitivity of 44% and 33.3%，respectively，with both had specificity of 100%，P<0.05);and the diagnostic cretria for CSF αFP could be empiricaly adjusted to ≥3.8 μg/L and for serum，αFP≥25 μg/L.After using the new criteria，the total diagnostic sensitivity for ICGCTs patients increased from 38.5% to 65.4%(mainly due to CSF β-hCG，weighted as above 90%).Since such a “evidence based medicine” conclusion was first reported in the international arena(original paper unpublished)，it can help to improve early and formal diagnosis of ICGCTs and of great clinical significance.

Key words: intracranial germ cell tumors, tumor markers；&beta, -subunit of human chorionic gonadotropin, alpha fetoprotein

摘要：

虽然通过病理结合肿瘤标志物已成为当前国际上确诊颅内生殖细胞肿瘤(ICGCTs)的共识，但是已有的“分泌性肿瘤”概念和三种经验性“高特异度”诊断标准［血清或脑脊液中人促绒毛膜激素(β-hCG)≥50 U/L或甲状腺胎蛋白(αFP)≥10 μg/L；β-hCG≥100 U/L或αFP≥50 μg/L；β-hCG>50 U/L或αFP>25 μg/L］并不符合当前诊断需要。为了进一步研究两者诊断价值，笔者在所在的北京协和医院组建了多学科综合诊断平台，并分析了医院1991-2012年确诊的ICGCTs病例(58例)的有效数据，得出了新的结论：明确了现有诊断标准之一［CSF/血清中β-hCG≥50 U/L和(或)αFP≥25 μg/L］的相对合理性；以疑似ICGCTs的病例作为阳性对照(17例)，用受试者工作曲线(ROC)计算出新的β-hCG诊断切点：CSF β-hCG≥8.4 U/L，血清β-hCG≥2.2 U/L(诊断敏感度分别为44%和33.3%，特异度均为100%，P<0.05)；发现CSF中αFP标准可下调为≥3.8 μg/L，血清αFP仍为≥25 μg/L。该标准可将总体诊断敏感度从38.5%提高至接近2/3(CSF的β-hCG的权重占90%以上)。通过在国际上首次报道此具有循证医学意义的新标准(论文待发表)，有助于改进对该病的早期和规范诊断。

关键词: 颅内生殖细胞肿瘤, 肿瘤标志物, 人促绒毛膜激素&beta, 亚单位, 甲胎蛋白