CK20免疫组化检测Ⅱ期直肠癌淋巴结微转移对结局的影响

Effect of Prognostic Outcome of Lymph Node Micrometastases of rectal Cancer Detected by CK20 Immunohistochemistry

目的：研究Ⅱ期直肠癌患者术后病理因素和CK20检测淋巴结微转移对患者结局的影响。方法对2006年12月至2009年12月行全直肠系膜切除的70例Ⅱ期直肠癌标本的743枚淋巴结行连续超薄切片结合cytokeratin-20（CK20）免疫组化染色检测，术后平均随访61.11（21~84）个月。根据随访资料分析Ⅱ期直肠癌患者系膜淋巴结微转移的临床意义。结果临床病理因素中，肿瘤的大小、分化程度、肠壁侵润深度、淋巴管浸润与否与CK20的表达呈正相关，其它因素与淋巴结CK20表达无明显相关性。在淋巴结CK20表达阳性、阴性患者中，5年无瘤生存率各为55.0%、75.6%，差异有统计学意义（P=0.010）。临床病理因素与5年无瘤生存率无明显相关性。结论免疫组化检测直肠癌淋巴结CK20表达可对直肠癌的分期、治疗方案的确定、预后的评估更准确合理。

Objective To evaluate the prognostic impact of a wide spectrum of pathologic parameters in a consecutive series of homogenously treated and well characterized patients with PT3-4N0M0 rectal cancer,rand the prognostic value of lymph node oc-cult disease（micrometastasis） in the five-year disease-free survival rates. Methods 70 with PT3-4N0M0 rectal tumors Undergone total mesorectal excision between January 2006 and March 2009 were enrolled. The average postoperative follow-up was 61.11 （21-84）months. 743 lymph nodes were studied in paraffin blocks that had Previously been considered free by conventional histopathological examination. These nodes were submitted to immunohistochemical analysis using CK20 monoclonal antibodies to identify micrometastasis. Five-year follow-up information was obtained on these patients. The survival rates abserved and assessed respectively in the patients with and without micrometastasis. Results Multivariate analysis identified size of tumor （＆lt;4cm or≥4;P=0.037）,lymphatic vessel invasion （absent or present;P=0.037） and depth of tumor invasion （T3 or T4;P=0.019） were positively correlated with CK20 expression. There was no significant correlative difference between pathologic parameters and the five-year disease-free survival rates. The five-year disease-free survival rates were 75.6 and 55.0 percent for the lymph node negative and micrometastasis groups,respectively. There was significant difference between the lymph node negative and micrometastasis groups （P=0.010）. Conclusions It is more accurate and reasonable in rectal cancer staging,treatment deciding and prognosis assessment that immunohistochemical mathod detects CK20 expression in lymph node of rectal cancer.