title: Lymphatic mapping improves staging during laparoscopic colectomy for cancer.
abstract: BACKGROUND
  Recently, lymphatic mapping (LM) of the sentinel lymph node (SN) has been coupled with ultrastaging methods to diagnose nodal micrometastases from colorectal cancer (CRC). We have developed a technique for LM at the time of laparoscopic colon resection (LCR).
  
  
  METHODS
  Between August 1996 and February 2000, 11 patients with small early-stage CRC underwent laparoscopic LM and LCR. The primary tumor/polyp site was visualized through a colonoscope and either tattooed preoperatively with a carbon dye (India ink), or stained intraoperatively by peritumoral injection of isosulfan blue dye. Immediately after intraoperative injection of blue dye, efferent lymphatic channels were visualized through the laparoscope and followed to the SN. Each blue-stained SN was marked with a suture or clip.
  
  
  RESULTS
  In all 11 cases, laparoscopic LM identified between one and three SN draining the primary tumor. LM added ~15-20 min to the operating time. The SN correctly reflected the nodal status of the entire specimen in all cases. In the one node-positive case, micrometastases were found only in an SN and only after cytokeratin immunohistochemistry (CK-IHC). In four cases, LM demonstrated unexpected primary lymphatic drainage that prompted an increase in the margins of resection.
  
  
  CONCLUSIONS
  LM during laparoscopic colectomy for CRC may be useful to mark the primary tumor site and to demonstrate lymphatic drainage that can alter the margins of resection. Focused examination of SN identifies occult micrometastases that up-stage CRC.
authors.affiliation: The John Wayne Cancer Institute, Saint John's Health Center, Department of Surgical Oncology, 2200 Santa Monica Boulevard, Santa Monica, CA 90404, USA.
authors.forename: T F
authors.initials: TF
authors.lastname: Wood
authors.forename: M
authors.initials: M
authors.lastname: Spirt
authors.forename: D
authors.initials: D
authors.lastname: Rangel
authors.forename: P
authors.initials: P
authors.lastname: Shen
authors.forename: G J
authors.initials: GJ
authors.lastname: Tsioulias
authors.forename: D L
authors.initials: DL
authors.lastname: Morton
authors.forename: A J
authors.initials: AJ
authors.lastname: Bilchik
mesh_terms: D000368:Aged; D003082:Colectomy / Q000379:methods*; D015179:Colorectal Neoplasms / Q000473:pathology* / Q000601:surgery*; D004801:Eosine Yellowish-(YS); D005240:Feasibility Studies; D005260:Female; D006416:Hematoxylin; D006801:Humans; D010535:Laparoscopy / Q000379:methods*; D008198:Lymph Nodes / Q000473:pathology* / Q000601:surgery; D008207:Lymphatic Metastasis; D008297:Male; D008875:Middle Aged; D021701:Sentinel Lymph Node Biopsy
chemical_list: D004801:Eosine Yellowish-(YS); D006416:Hematoxylin