MC5免疫组织化学在大肠癌中的定位诊断研究

目的 研究免疫组织化学法检测MC5在大肠癌定位诊断中的意义.方法 选取2014年1月至2015年2月在我校附属医院病理科存档的确诊为大肠癌的蜡块标本102例及内镜中心活检病理为正常粘膜的40例,通过免疫组化法检测102例大肠癌和40例正常人群粘膜的MC5表达水平,研究其在大肠癌早期定位诊断中的价值.结果 40例正常人群的粘膜MC5表达均为阴性,102例大肠癌患者的MC5阳性表达率为89.21％(91/102),且定位于胞浆和胞膜,在癌旁正常组织中MC5阳性表达率为37.25％(38/102),两者相较差异有统计学意义(P＜0.05).在35例高分化癌中,表达结果为-的7例,+的20例,++的4例,+++的4例;在28例中分化癌中,表达结果为-的4例,+的4例,++的17例,+++的3例;在39例低分化癌中,表达结果为-的0例,+的6例,++的2例,+++的31例;MC5表达水平与大肠癌的分化程度呈负相关,MC5表达水平随着分化程度的上升而下降.结论 MC5在大肠癌中呈阳性表达,具有一定的特异性,且分化程度越低表达水平越高,可作为大肠癌早期定位诊断的指标之一.

MC5 immunohistochemistry in localization diagnosis of colorectal cancer

Objective To study clinical significance of MC5 immunohistochemical assay in localization diagnosis of colorectal cancer.Methods 102 cases of paraffin blocks of specimens biopsy diagnosed with colorectal cancer from pathology department of affiliated hospital of our school and 40 cases of normal mucosa from endoscopy center from January 2014 to February 2015 were selected.Detected the expression level of MC5 in 102 cases of colorectal cancer and 40 cases of normal mucosa by immunohistochemistry,investigated its value in early localization diagnosis of colorectal cancer.Results MC5 mucosal expression in 40 cases of normal population was negative.MC5 positive expression rate was 89.21％ (91/102) in 102 cases of colorectal cancer,and located in cytoplasm and cell membrane;MC5 positive expression rate in adjacent normal tissues was 37.25％ (38/102),with statistically significant difference (P＜0.05).In 35 cases of well-differentiated carcinoma,there were 7 cases with the expression result of-,20 cases of +,4 cases of ++,4 cases of +++;in 28 cases of differentiated carcinoma,there were 4 cases with the expression result of-,4 cases of+,17 cases of++,3 cases of+++;in 39 cases of poorly differentiated carcinoma,there were 6 cases with the expression result of+,2 cases of ++,31 cases of +++;the expression level of MC5 was negatively correlated to the differentiation degree of colorectal cancer.Conclusions MC5 shows positive expression in colorectal cancer,with some specificity,and the expression level of MC5 is negatively correlated to the differentiation degree of colorectal cancer,which can be used as an indicator of early localization diagnosis of colorectal cancer.