摘要目的 探讨采用经肠系膜下动脉注射美蓝法增加新辅助化疗后直肠癌手术标本淋巴结检出数的可行性.方法 以2011年1月至2013年12月期间中山大学附属第三医院胃肠外科接受新辅助化疗和后续根治性切除手术的42例中低位直肠癌患者为研究对象.先后采用传统触摸法和经肠系膜下动脉注射美蓝法在同一标本上检获淋巴结,结果用配对t检验和交叉分类资料的x2检验进行统计学分析.结果 42例手术标本用传统触摸法检出淋巴结平均(6.1±4.3)枚/例,其中转移淋巴结80枚(17例).标本进一步循美蓝染色多检出382枚淋巴结.经过两次处理后42例直肠癌标本共检出淋巴结枚(15.2±6.4)枚/例,转移淋巴结93枚(18例),其中46.7％为直径≤5 mm的小淋巴结.统计学分析提示两种方法所得淋巴结数目的差异有统计学意义(P＜0.001),而两组的转移淋巴结(N+)病例数差异无统计学意义(P=0.89).结论 肠系膜下动脉美蓝注射法可增加新辅助化疗后直肠癌标本淋巴结的检获,发现更多小淋巴结和转移淋巴结,提供更准确的分期.

abstractsObjective To confirm the feasibility of improving lymph node harvest by injecting methylene blue into inferior mesenteric artery in rectal cancer after neoadjuvant therapy.Methods Forty two ex vivo specimens were collected from rectal cancer patients with neoadjuvant therapy and radical operation at our hospital.Traditional method with palpation and injection of methylene blue into inferior mesenteric artery were employed.The data of lymph node harvest were analyzed by paired t and chi-square tests.Results The average number of detected lymph node in traditional method and methylene blue groups were 6.1 ± 4.3 and 15.2 ± 6.4 respectively (P ＜ 0.001).The proportions of lymph nodes ＜ 5 mm were 14.1％ and 46.7％ in traditional method and methylene blue groups respectively (P ＜ 0.001).And the injection of methylene blue added 13 extra metastatic lymph nodes and caused a shift to node-positive stage (P =0.89).Conclusion Neoadjuvant therapy decrease lymph node retrieval in rectal cancer.Injecting methylene blue into inferior mesenteric artery improves lymph node harvest especially for small nodes and helps to acquire more metastatic nodes for accurate pathological staging.