title: 5-Aminolevulinic Acid Fluorescence in Detection of Peritoneal Metastases.
abstract: BACKGROUND
  The value of 5-aminolevulinic acid (ALA) in fluorescence detection of peritoneal metastases and the underlying mechanisms were evaluated in patients with peritoneal surface malignancies.
  
  
  METHODS
  Oral 5-ALA was administered at a concentration of 20 mg ⁄kg body weight with 50 ml of water 2 hours prior to surgery (n=115). The diagnostic value of 5-ALA based fluorescence production was evaluated following white light inspection during prior to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy. Then, peptide transporter PEPT1 (ALA influx transporter) and ATP-binding cassette transporter ABCG2 (porphyrin efflux transporter) gene expression was determined with quantitative real time (qRT)-PCR and pathological diagnoses confirmed for all tissue samples.
  
  
  RESULTS
  The 5-ALA based photodynamic detection rate was 17% for appendiceal mucinous neoplasms, 54% for colorectal cancers, 33% for gastric cancers, 67% for diffuse malign peritoneal mesotheliomas, and 89% for epithelial ovarian cancer of peritoneal metastases. 5-ALA was detected in all cases of peritoneal metastases originating from cholangiocarcinomas whereas it was not able to detect any in granulosa cell and gastrointestinal stromal tumor cases. Furthermore, PEPT1 was overexpressed whereas ABCG2 expression was downregulated in tumors detected with fluorescence.
  
  
  CONCLUSIONS
  5-ALA provided 100% specificity and high sensitivity to detect peritoneal metastases in subgroups of patients with peritoneal surface mailgnancies. ALA influx transporter PEPT1 and porphyrin efflux transporter ABCG2 genes are important in tumor specific 5-ALA induced fluorescence in vivo. Further studies should clarify diagnostic utility of 5-ALA in peritoneal surface malignancies.
authors.affiliation: NPO Organization to support Peritoneal Dissemination Treatment, 1-26, Harukimotomachi, Kishiwada City, Osaka, Japan E-mail : drecanbay@gmail.com.
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Yonemura
authors.forename: Emel
authors.initials: E
authors.lastname: Canbay
authors.forename: Haruaki
authors.initials: H
authors.lastname: Ishibashi
authors.forename: Eisei
authors.initials: E
authors.lastname: Nishino
authors.forename: Yoshio
authors.initials: Y
authors.lastname: Endou
authors.forename: Shouzou
authors.initials: S
authors.lastname: Sako
authors.forename: Shun-Ichirou
authors.initials: S
authors.lastname: Ogura
mesh_terms: D000622:Aminolevulinic Acid / Q000008:administration & dosage*; D065426:Cytoreduction Surgical Procedures; D005260:Female; D005453:Fluorescence; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology* / Q000601:surgery; D010534:Peritoneal Neoplasms / Q000378:metabolism / Q000556:secondary* / Q000601:surgery; D017319:Photosensitizing Agents / Q000008:administration & dosage*; D011379:Prognosis
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid