title: 5-aminolevulinic acid (5-ALA)-induced fluorescence in intracerebral metastases: a retrospective study.
abstract: BACKGROUND
  Microsurgical, circumferential stripping of intracerebral metastases often proves to be insufficient to prevent local tumor recurrence.
  
  
  OBJECTIVE
  We were interested in the potential impact of 5-aminolevulinic acid (5-ALA)-induced-fluorescence (5-AIF) as a diagnostic tool for the resection of intracerebral metastases.
  
  
  METHODS
  A retrospective analysis was performed for 52 patients who underwent 5-AIF-guided resection for intracerebral mass lesions that histologically corresponded to metastases from tumors outside the central nervous system. The presence of ALA fluorescence in the tumor was determined in each patient. In 42 patients, fluorescence of the resection cavity after tumor removal was additionally recorded. Data were correlated with neuropathological findings in tissue specimens.
  
  
  RESULTS
  A total of 32 of the 52 metastases (62%) exhibited 5-AIF in tumor parts. All 5-AIF-positive metastases exhibited an inhomogeneous fluorescence pattern. 5-AIF was neither associated with the histological type nor with the site of origin of the metastases. Residual fluorescence of the resection cavity was detected after macroscopically complete white light resection in 24 patients with 5-AIF positive metastases. Residual tumor tissue was histologically confirmed in 6 of 18 patients with available tissue specimens from such 5-AIF positive areas (33%).
  
  
  CONCLUSIONS
  The majority of metastases (62%) were 5-AIF positive, suggesting a potential impact of 5-AIF for improved visualization of metastatic tumor tissue within the brain. However, residual 5-AIF after macroscopically complete resection of a metastasis needs to be interpreted with caution because of the limited specificity for detection of residual tumor tissue.
authors.affiliation: Neurochirurgische Klinik, Heinrich-Heine-Universität Düsseldorf, Moorenstraße 5, Geb. 13.71, 40225 Düsseldorf, Germany. marcelalexander.kamp@uni-duesseldorf.de
authors.forename: Marcel A
authors.initials: MA
authors.lastname: Kamp
authors.forename: Philipp
authors.initials: P
authors.lastname: Grosser
authors.forename: Jörg
authors.initials: J
authors.lastname: Felsberg
authors.forename: Philipp J
authors.initials: PJ
authors.lastname: Slotty
authors.forename: Hans-Jakob
authors.initials: HJ
authors.lastname: Steiger
authors.forename: Guido
authors.initials: G
authors.lastname: Reifenberger
authors.forename: Michael
authors.initials: M
authors.lastname: Sabel
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology / Q000556:secondary / Q000601:surgery; D000368:Aged; D000369:Aged, 80 and over; D000622:Aminolevulinic Acid; D001932:Brain Neoplasms / Q000473:pathology* / Q000556:secondary* / Q000601:surgery; D002277:Carcinoma / Q000473:pathology* / Q000556:secondary* / Q000601:surgery; D005260:Female; D005453:Fluorescence; D006801:Humans; D008297:Male; D008545:Melanoma / Q000473:pathology* / Q000556:secondary* / Q000601:surgery; D008875:Middle Aged; D017319:Photosensitizing Agents; D011300:Preoperative Care; D012189:Retrospective Studies
chemical_list: D017319:Photosensitizing Agents; D000622:Aminolevulinic Acid