CD56在小细胞癌组织中的表达及其对诊断的作用

背景与目的:小细胞癌(smallcellcarcinoma,SCC)是恶性度及死亡率高的少见恶性肿瘤,临床病理目前常用神经特异性烯醇化酶(neuron-specificenolase,NSE),触突素(synaptophysin,SYN),嗜铬蛋白(chromograninA,CgA)标记协助诊断,本项目拟研究CD56在小细胞癌组织中的表达并探讨把CD56作为临床病理诊断小细胞癌的标记分子的可能性。方法:收集小细胞癌病例标本共80例,包括肺原发病例42例,其中伴淋巴结转移20例;食管原发病例21例,结直肠原发病例17例。另外随机选取肺非小细胞癌38例作为对照(肺鳞癌26例,肺腺111癌12例),其中淋巴结转移28例。所有标本用CD56,NSE,Syn,CgA,CK和EMA进行免疫组化染色。结果:CD56在肺小细胞癌肿瘤组织及其淋巴结转移灶组织中阳性率显著高于在肺非小细胞癌中阳性率,其在肺小细胞癌原发灶阳性率为90.5%(38/42),转移灶为90.0%(18/20),其在肺非小细胞癌原发灶阳性率为7.8%(3/38),转移灶为3.5%(1/28)(H=85.731,P<0.001),它在小细胞癌肿瘤组织中阳性率明显高于NSE,CgA,CK与EMA的阳性率,其阳性率分别为:CD5686.3%(69/80),Syn78.8%(63/80),CgA73.8%(59/80),EMA66.3%(53/80),CK61.3%(49/80),NSE56.3%(45/80)(H=38.871,P<0.001)。CD56在肺、食管及结直肠小细胞癌中阳性率比较无显著差异,其阳性率分别为肺90.5%(38/42),食管81.0%(17/21),结直肠82.4%(14/17)(H=1.651,P=0.438)。结论:CD56在小细胞癌组织中无论是原发灶还是淋巴结转移灶的阳性率均高,且无器官特异性;CD56可作为临床病理诊断小细胞癌的阳性标记物。

Expression of CD56, as a potential diagnostic marker, in small cell carcinoma

BACKGROUND & OBJECTIVE: Small cell carcinoma is a rare malignant disease with high mortality, which is pathologically diagnosed by using routine neuroendocrinal markers, such as neuron-specific enolase (NSE), synaptophysin (SYN), chromogranin A (CgA). This study was to investigate the expression of CD56, a neural cell adhesion molecule (NCAM), in small cell carcinoma tissues, and to explore the possibility of CD56 as a diagnostic marker of small cell carcinoma. METHODS: Eighty samples of small cell carcinoma were collected, including 42 samples of small cell lung carcinoma (with 20 cases of lymph node metastases), 21 samples of small cell esophageal carcinoma, and 17 samples of small cell colorectal carcinoma. Thirty-eight samples of non-small cell lung cancer (with 28 cases of lymph node metastases), including 26 samples of squamous cell carcinoma and 12 samples of adenocarcinoma, were used as control. All samples were detected using markers of CD56, NSE, SYN, CgA, cytokeratin (CK), and epithelial membrane antigen (EMA) immunohistochemically. RESULTS: Positive rate of CD56 was significantly higher in either small cell lung carcinoma or their metastatic lymph nodes than in either non-small cell lung carcinoma or their metastatic lymph nodes [90.5% (38/42) vs. 7.8% (3/38), 90.0% (18/20) vs. 3.5% (1/28); H=85.731, P<0.001]. Positive rate of CD56 in small cell carcinoma samples (86.3%, 69/80) were significantly higher than those of SYN (78.8%, 63/80), CgA (73.8%, 59/80), EMA (66.3%, 53/80), CK (61.3%, 49/80), and NSE (56.3%, 45/80) (H=38.871,P<0.001). Positive rate of CD56 in small cell lung carcinoma (90.5%,38/42) was similar to those in small cell esophageal carcinoma (81.0%, 17/21) and small cell colorectal carcinoma (82.4%,14/17) (H=1.651, P=0.438). CONCLUSIONS: CD56 is highly expressed in either small cell carcinoma or their metastatic lymph nodes without organ-specificity. It could serve as a potential diagnostic marker of small cell carcinoma.