表皮生长因子受体在中耳胆脂瘤中的异常表达

目的：观察表皮生长因子受体（EGFR）在中耳继发性胆脂瘤中的表达情况，分析其在胆脂瘤上皮增殖演变过程的作用。方法：应用免疫组化SP染色方法和计算机图像分析系统，检测20例胆脂瘤上皮，10例术腔内肉芽组织，10例鼓膜穿孔部位邻近皮肤和20例耳道深部正常皮肤中EGFR的表达情况。结果：胆脂瘤上皮各层细胞中EGFR均高度表达，以基底层和棘层为；鼓膜穿孔部位邻近皮肤则在基底层和棘层细胞中等表达，耳道深部正常皮肤仅基底层弱表达；肉芽组织内存在散在的阳性细胞。胆脂瘤上皮和鼓膜穿孔部位邻近皮肤及耳道深部正常皮肤之间差异均具有高度显性（P＜0．001）。鼓膜穿孔部位邻近皮肤和耳道深部正常皮肤之间差异亦均具有高度显性（P＜0．01）。结论：EGFR在中耳继发性胆脂瘤中不同部位的表达呈连续性阶梯性上升；在胆脂瘤上皮中的高表达，说明胆脂瘤上皮具有高度增殖能力。

Continuous expression of EGFR in human middle ear cholesteatoma

Objective:To observe the expressions of EGFR in acquired middle ear cholesteatoma and to analyze the role of EGFR playing in proliferation of cholesteatoma epidermis.Methods:The specimens from the acquired middle ear cholesteatoma tissue of 20 cases?the granulation tissue of 10 cases?the adjacent skin around perforation of 10 cases and the normal external ear skin of 20 cases were examined by immunohistochemical S-P method and computer image analysis.Results:The expression of EGFR in all epithelial layers of cholesteatoma were abundantly stained,especially in the basal and spinous layers; the basal and spinous layers were middle stained in the adjacent skin around perforation;and only the basal layer were slightly stained in the normal external ear skin; the granulation tissue was scatteredly stained.There was significant differences between cholesteatoma tissue and the adjacent skin around perforation,or between cholesteatoma tissue and the normal external ear skin(P<0.001). There was distinctly significant difference between the adjacent skin around perforation and the normal external ear skin(P<0.01).Conclusion:There was a spiral increase of EGFR expression from the normal external ear skin to the cholesteatoma epidermis. EGFR played a key role in the differentiation and the hyperproliferation of cholesteatoma.