摘要目的 探讨CIC蛋白失表达在少突胶质细胞肿瘤中作为预测染色体1p/19q共缺失初筛检测方法的可行性及其对预后的影响.方法 回顾性分析首都医科大学宣武医院病理科113例形态学具有少突胶质细胞瘤特征的胶质瘤,分别进行染色体1p/19q共缺失荧光原位杂交(FISH)检测及CIC蛋白免疫组织化学标记.分析CIC蛋白失表达与染色体1p/19q共缺失的相关性,并探讨其与预后的关系.结果 在113例组织学诊断为少突胶质细胞肿瘤中,CIC蛋白失表达率为59.3%(67/113),不同的组织学类型中失表达率不同,在只含有少突胶质细胞成分的肿瘤中失表达率(85.7%,42/49)比混合性的胶质瘤中(39.1%,25/64)高(P<0.01).CIC蛋白失表达预测1p/19q共缺失的敏感性和特异性分别为76.1%(54/71)和71.1%(27/38),假阳性率和假阴性率分别为16.9%(11/65)和38.6%(17/44).按照2016版《WHO中枢神经系统肿瘤分类第4版修订版》,本组病例中63例整合诊断符合少突胶质细胞瘤/间变型少突胶质细胞瘤,IDH突变及1p/19q共缺失;CIC蛋白失表达率为81.0%(51/63),其预测1p/19q共缺失的敏感性和特异性分别提高至81.0%(51/63)和76.9%(20/26),假阳性率和假阴性率分别降至10.5%(6/57)和37.5%(12/32).此时,应用Kaplan-Meier法分析CIC蛋白失表达对预后的影响,发现CIC蛋白失表达组比阳性表达组预后稍好,但二者差异无统计学意义(总生存期:P=0.218;无进展生存期:P=0.249).结论 利用免疫组织化学检测CIC蛋白失表达情况,可以作为染色体1p/19q共缺失的一种初筛检测方法.CIC蛋白失表达与预后无关.

abstractsObjective To investigate the usefulness of loss of CIC expression as the prescreening detection of 1p/19q co-deletion in the diagnosis of oligodendroglial tumors and its prognostic implication. Methods The retrospective study included 113 oligodendroglial tumors diagnosed in the Department of Pathology, Xuanwu Hospital, Capital Medical University. Expression of CIC protein was detected by immunohistochemistry, and the 1p/19q co-deletion by fluorescence in situ hybridization in all the tumors;and the correlation of the loss of protein and 1p/19q co-deletion with prognosis was assessed. Results The rate of negative CIC protein expression was 59. 3% ( 67/113) in 113 oligodendroglial tumors. CIC protein expression was differentially lost in various gliomas, 85. 7% (42/49) in pure oligodendrogliomas and 39.1%( 25/64) in mixed oligodendroglial tumors ( P<0. 01 ) . The loss of CIC protein expression showed a sensitivity of 76. 1% (54/71), specificity 71. 1% (27/38), false positive rate of 16. 9% (11/65), and a false negative rate of 38. 6% ( 17/44 ) . In 63 cases integrated diagnosis as oligodendroglial tumors with mutant IDH and 1p/19q co-deletion, the loss of CIC protein expression was 81. 0% ( 51/63);the sensitivity and specificity were increased to 81. 0% ( 51/63) and 76. 9% ( 20/26) , and the false positive rate and falsenegative rate decreased to 10. 5% ( 6/57 ) and 37. 5% ( 12/32 ) , respectively. By using Kaplan-Meier analysis, the CIC negative group showed a trend towards better outcome than the CIC positive group, but there was no statistical difference ( overall survival: P=0. 218; progression free survival: P=0. 249 ) . Conclusions Detection of the lost CIC protein expression can predict the chromosome 1p/19q co-deletion. In oligodendroglial tumors with IDH mutant and 1p/19q co-deletion, there is no relation between prognosis and CIC protein expression.