Expression and clinical significance of EGFR, PCNA, Bcl-2 and Bax in thymoma

Objective:To study the expressions and clinical significances of PCNA, EGFR, Bcl-2 and Bax in thymoma. Methods: The expressions of EGFR, PCNA, Bcl-2 and Bax in 46 cases of thymoma and 11 cases of normal thymus were detected with S-P immunohistochemistry. The results were analyzed with the pathologic indexes. Results: The positive rates of EGFR, Bcl-2 and Bax in normal thymus were 18. 2%, 9. 1%,and 18.2% respectively, while in thymoma were 71.7%, 41.3%, and 15.2% separately. The expression of EGFR in thymoma was significantly correlated with Masaoka staging and Levine classification. The survival rate of EGFR negative patients was significantly higher thanthat of EGFR positive patients (P＜0. 01). PCNA labelling index was significantly higher in thymoma as (4.00±1.87)% than in normal thymus, (2.68±0. 62)% , which was significantly correlated with Levine classification. The expression of Bcl-2 in thymoma was also significantly correlated with Levine classification. The survival rate of Bcl-2 negative patients was significantly higher than that of Bcl-2 positive patients (P＜0. 01). The expression of PCNA, EGFR, Bcl-2and Bax in thymoma had no correlation with histologic type and myasthenia gravis (MG) (P＞0. 05). Conclusion: The expression of EGFR may be involved in the occurrence and development of thymoma. EGFR can be regarded as a supplementary predictor for Masaoka staging so as to predict the progression accurately.The expression of Bcl-2 may contribute to the occurrence of thymic carcinoma and Bcl-2 can be used as a biomarker identifying thymic carcinoma.

PCNA表达与胸腺瘤病理分型及临床分期的相关性分析

目的 研究胸腺瘤中的增殖细胞核抗原 (PCNA )表达 (增殖指数 ,PI)与病理分型和临床分期的相关性。方法 对 5 1例胸腺瘤采用免疫组织化学方法检测PCNA表达 ,并与Masaoka′s临床分期及M M病理组织学分型结果作相关性分析。结果 A组 (非侵袭性胸腺瘤 ) 2 3例 ;B组 (侵袭性胸腺瘤 ) 2 1例 ;C组 (胸腺癌 ) 7例 ,PCNA表达阳性大多为上皮样分化的瘤细胞。临床Ⅰ期 2 5例 ;Ⅱ期 10例 ;Ⅲ期 9例 ;Ⅳ期 7例。统计学分析提示 :PI与病理分型有显著的相关性 (F =7.40 ,P <0 .0 1) ,尤其是A组与B、C组比较有显著性差异 (P <0 .0 1) ,但在B、C组之间无差异 (P >0 .0 5 ) ;PI与临床分期之间亦有显著的相关性 (F =8.5 4,P <0 .0 1) ,其中Ⅰ期与Ⅱ期有显著性差异 (P <0 .0 5 ) ,Ⅰ期与Ⅲ、Ⅳ期之间有非常显著性差异 (P <0 .0 1) ,Ⅱ、Ⅲ、Ⅳ期之间无差异 (P >0 .0 5 )。病理分型与临床分期有显著的相关性 (χ2 =2 9.2 6 ,P <0 .0 1,C =0 .385 )。结论 PCNA表达的检测 (PI)与胸腺瘤的病理分型和临床分期呈正相关 ,反映了胸腺瘤的侵袭潜能和恶性程度。

重症肌无力合并胸腺瘤的临床特点及细胞核增殖相关抗原的表达

目的探讨重症肌无力(MG)合并胸腺瘤的临床特点和细胞核增殖相关抗原(PCNA)的表达。方法选择25例伴有MG的胸腺瘤患者(MG组)和25例不伴有MG的胸腺瘤患者(非MG组),采用免疫组化法检测患者胸腺瘤组织中PCNA的表达,阳性为棕黄色颗粒;记录在放大100倍的油镜下随机计数1000个肿瘤细胞中的阳性细胞率。结果MG组中5例发生肌无力危象,其中1例死亡。伴重症肌无力的瘤性细胞群主要含有PCNA低表达的细胞。结论伴重症肌无力的胸腺瘤组织恶性程度相对较低,淋巴细胞型的胸腺瘤患者易伴发重症肌无力。