title: Indocyanine green fluorescence-navigated sentinel node biopsy showed higher sensitivity than the radioisotope or blue dye method, which may help to reduce false-negative cases in skin cancer.
abstract: OBJECTIVE
  Although sentinel lymph node (SLN) biopsy using radioisotope (RI) and blue dye (BD) achieved a high detection rate, approximately 5% of melanomas with negative SLNs develop nodal metastasis. We tested a new lymphatic navigation method using indocyanine green fluorescence imaging (ICG-FI) to detect such "occult" SLNs.
  
  
  METHODS
  Thirty-four skin cancer patients received SLN biopsy with the following three methods: RI (99Tc-tin colloid), BD (2% patent blue), and ICG (0.5% indocyanine green). Lymph nodes detected by any of the three methods were counted as SLNs.
  
  
  RESULTS
  ICG-FI detected more SLNs in 8 out of the 34 cases (24%). The average numbers of SLNs detected by ICG-FI, RI, and BD were 2.18, 1.76, and 1.73, respectively. Interestingly, ICG-FI not only detected more SLNs in one basin (ICG-FI: 1.64, RI: 1.50, and BD: 1.51 SLNs per basin), but also detected additional SLNs in other basins (ICG-FI: 1.32, RI: 1.18, and BD: 1.15 basins per case).
  
  
  CONCLUSIONS
  ICG-FI detected SLNs more efficiently than did the conventional methods, and these "occult" SLNs may offer an explanation for some false-negative cases. We recommend using ICG-FI in addition to a conventional method to reduce the risk of overlooking these "occult" SLNs.
authors.affiliation: Division of Dermatology, University of Tsukuba, Tsukuba City, Ibaraki, Japan. fujisan@md.tsukuba.ac.jp
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Fujisawa
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kawachi
authors.forename: Fujio
authors.initials: F
authors.lastname: Otsuka
mesh_terms: D000328:Adult; D000368:Aged; D015266:Carcinoma, Merkel Cell / Q000473:pathology; D002294:Carcinoma, Squamous Cell / Q000473:pathology; D004396:Coloring Agents; D005188:False Negative Reactions; D005260:Female; D005456:Fluorescent Dyes; D006801:Humans; D007208:Indocyanine Green; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis / Q000175:diagnosis; D008297:Male; D008545:Melanoma / Q000473:pathology; D008875:Middle Aged; D010145:Paget Disease, Extramammary / Q000473:pathology; D019275:Radiopharmaceuticals; D012189:Retrospective Studies; D012394:Rosaniline Dyes; D012680:Sensitivity and Specificity; D021701:Sentinel Lymph Node Biopsy / Q000379:methods*; D012878:Skin Neoplasms / Q000473:pathology*; D013544:Sweat Gland Neoplasms / Q000473:pathology; D017556:Technetium Compounds; D017971:Tin Compounds
chemical_list: D004396:Coloring Agents; D005456:Fluorescent Dyes; D019275:Radiopharmaceuticals; D012394:Rosaniline Dyes; D017556:Technetium Compounds; D017971:Tin Compounds; C033493:technetium Tc 99m tin colloid; C008769:sulfan blue; D007208:Indocyanine Green