title: Intraoperative Detection of Superficial Liver Tumors by Fluorescence Imaging Using Indocyanine Green and 5-aminolevulinic Acid.
abstract: OBJECTIVE
  Indocyanine green (ICG) and the porphyrin precursor 5-aminolevulinic acid (5-ALA) have been approved as fluorescence imaging agents in the clinical setting. This study evaluated the usefulness of fluorescence imaging with both ICG and 5-ALA for intraoperative identification of latent small liver tumors.
  
  
  METHODS
  There were 48 patients who had main tumors within 5 mm of the liver surface. 5-ALA hydrochloride was orally administered to patients 3 h before surgery. ICG had been intravenously injected within 14 days prior to surgery. Intraoperatively, after visual inspection, manual palpation and ultrasonography fluorescence images of the liver surface were obtained with ICG and 5-ALA prior to resection.
  
  
  RESULTS
  With ICG, the sensitivity, specificity and accuracy for detecting the preoperatively identified main tumors were 96%, 50% and 94%, respectively. Twelve latent small tumors were newly detected on the liver surface using ICG, five of which proved to be carcinomas. With 5-ALA, the sensitivity, specificity and accuracy for detecting the main tumors were 57%, 100% and 58%, respectively. Five latent small tumors were newly detected using 5-ALA; all were carcinomas. Overall, five new tumors were detected by both ICG and 5-ALA fluorescence imaging; two were hepatocellular carcinomas (HCCs) and three were metastases of colorectal cancer. The sensitivity and specificity of ICG fluorescence imaging for main tumor detection were relatively high and low, respectively, but the opposite was true of 5-ALA imaging.
  
  
  CONCLUSIONS
  Fluorescence imaging using 5-ALA may provide greater specificity in the detection of surface-invisible malignant liver tumors than using ICG fluorescence imaging alone.
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan kaibori@hirakata.kmu.ac.jp.
authors.forename: Masaki
authors.initials: M
authors.lastname: Kaibori
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Matsui
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Morihiko
authors.initials: M
authors.lastname: Ishizaki
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Hiroya
authors.initials: H
authors.lastname: Iida
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Tadayoshi
authors.initials: T
authors.lastname: Okumura
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Tatsuma
authors.initials: T
authors.lastname: Sakaguchi
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Inoue
authors.affiliation: Third Department of Internal Medicine, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Tsukasa
authors.initials: T
authors.lastname: Ikeura
authors.affiliation: School of Nursing, Kyoto Prefectural University of Medicine, Kyoto, Japan.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Asano
authors.affiliation: Department of Surgery, Hirakata Hospital, Kansai Medical University, Hirakata, Osaka, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Kon
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000622:Aminolevulinic Acid / Q000009:adverse effects; D003952:Diagnostic Imaging / Q000379:methods; D005260:Female; D005453:Fluorescence; D005456:Fluorescent Dyes / Q000009:adverse effects; D006498:Hepatectomy; D006801:Humans; D007208:Indocyanine Green; D008113:Liver Neoplasms / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000601:surgery; D008297:Male; D008875:Middle Aged; D012680:Sensitivity and Specificity; D014463:Ultrasonography
chemical_list: D005456:Fluorescent Dyes; D000622:Aminolevulinic Acid; D007208:Indocyanine Green
keywords: 5-aminolevulinic acid; Liver tumor; hepatic resection; indocyanine green; intraoperative fluorescent imaging