title: Fluorescence imaging after intraoperative intravenous injection of indocyanine green for detection of lymph node metastases in colorectal cancer.
abstract: OBJECTIVE
  This short communication aims at reporting the potential role of ICG fluorescence imaging after an intraoperative IV injection in the detection of lymph nodes (LNs) of a colorectal cancer origin.
  
  
  METHODS
  Two patients who were included in a protocol study evaluating the role of ICG in the detection of peritoneal metastases of colorectal origin (Protocol NCT-01995591) also had fluorescent LNs at exploration with a dedicated near-infrared camera system (Photodynamic Eye, PDE; Hamamatsu Photonics, Hamamatsu, Japan). An IV injection of ICG was delivered intraoperatively at 0.25 mg/kg. All LNs were also explored for their fluorescence, and tumor to background ratio (TBR) was calculated with IC-Calc 2.0 program.
  
  
  RESULTS
  One patient had two retroperitoneal lymph node metastases and one mesocolic on a pre-operative work-up. The three tumoural lymph nodes at histopathology were hyperfluorescent in comparison to other uninvolved LNs. One patient had no pre-operatively known LN metastases and had one epigastric hyperfluorescent LN discovered at intraoperative exploration. This LN of 6 mm in size was malignant at histopathology.
  
  
  CONCLUSIONS
  This is the first report about tumoural LN of colorectal cancer origin detected by fluorescence imaging with intraoperative IV free-ICG injection. ICG fluorescence imaging by intraoperative IV injection represents an easy method for detecting metastatic LNs in colorectal cancer. This proof of concept should lead to further research in this field.
authors.affiliation: Department of Surgical Oncology, Institut Jules Bordet, Université Libre de Bruxelles (ULB), 1000 Brussels, Belgium. Electronic address: gabriel.liberale@bordet.be.
authors.forename: G
authors.initials: G
authors.lastname: Liberale
authors.affiliation: Department of Nuclear Medicine and Clinic-Unit of Lymphology, Institut Jules Bordet, Université Libre de Bruxelles (ULB), 1000 Brussels, Belgium. Electronic address: Sophie_VANKERCKHOVE@stpierre-bru.be.
authors.forename: S
authors.initials: S
authors.lastname: Vankerckhove
authors.affiliation: Department of Anatomo-Pathology, Institut Jules Bordet, Université Libre de Bruxelles (ULB), 1000 Brussels, Belgium. Electronic address: maria.gomezgaldon@bordet.be.
authors.forename: M G
authors.initials: MG
authors.lastname: Galdon
authors.affiliation: Department of Surgical Oncology, Institut Jules Bordet, Université Libre de Bruxelles (ULB), 1000 Brussels, Belgium. Electronic address: Vincent.donckier@bordet.be.
authors.forename: V
authors.initials: V
authors.lastname: Donckier
authors.affiliation: Department of Anatomo-Pathology, Institut Jules Bordet, Université Libre de Bruxelles (ULB), 1000 Brussels, Belgium. Electronic address: denis.larsimont@bordet.be.
authors.forename: D
authors.initials: D
authors.lastname: Larsimont
authors.affiliation: Department of Nuclear Medicine and Clinic-Unit of Lymphology, Institut Jules Bordet, Université Libre de Bruxelles (ULB), 1000 Brussels, Belgium. Electronic address: pierre.bourgeois@bordet.be.
authors.forename: P
authors.initials: P
authors.lastname: Bourgeois
mesh_terms: D000230:Adenocarcinoma / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D015179:Colorectal Neoplasms / Q000175:diagnosis / Q000473:pathology* / Q000601:surgery; D004396:Coloring Agents; D005260:Female; D006801:Humans; D007208:Indocyanine Green; D007275:Injections, Intravenous; D007430:Intraoperative Care; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008646:Mesocolon; D008875:Middle Aged; D061848:Optical Imaging / Q000379:methods*; D011446:Prospective Studies; D012187:Retroperitoneal Space; D012680:Sensitivity and Specificity
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green
keywords: Colorectal cancer; Epigastric para-aortic lymph nodes; Fluorescence imaging; NIR (near-infrared)