RESUMO
Objective To explore the value of lymphatic mapping (LM) and sentinel lymph node(SLN) analysis in laparoscopic colectomy for colon carcinoma. Methods Thirty-two patients with clinically localized colonic neoplasms were subjected to submucosal injection of isosulfan blue dye (0.5-1.0 mL) via a colonoscope during operation. Blue-stained lymphatics were visualized through the laparoscope and followed to the SLN,which was tagged. The colectomy was completed in standard fashion. All lymph nodes were stained by hematoxylin and eosin,and multiple sections of each SLN were examined by immunohistochemical (IHC) staining using cytokeratin antibody. Results At least one SLN was identified laparoscopically in all patients. The SLN accurately predicted the tumor status of the nodal basin in 94% of cases. In 8 cases (25%),an unexpected lymphatic drainage pattern altered the extent of mesenteric resection. The SLN was negative by HE staining in 4 (13%) cases,which were demonstrated positive for micrometastases through immunohistochemical staining. Conclusions SLN mapping during laparoscopic colon resection can alter the margins of resection and in combination with immunohistochemical staining may improve staging,which may more accurately assign patients to prospective protocols.