title: Predictive value of intraoperative 5-aminolevulinic acid-induced fluorescence for detecting bone invasion in meningioma surgery.
abstract: OBJECTIVE
  Bone invasion is a major concern in meningioma surgery, since it is predictive of the recurrence of cranial involvement, morbidity, and mortality. Bone invasion has been reported in 20%-68% of studies with histopathologically confirmed data. Unfortunately, radical resection of bone invasion remains challenging. The aim of this study was to assess the role of 5-aminolevulinic acid (5-ALA) fluorescence in guiding the resection of bone-invading meningiomas. To this purpose, the sensitivity, specificity, and positive and negative predictive values of 5-ALA in detecting meningioma bone invasion were evaluated.
  
  
  METHODS
  Data from 12 patients affected by bone-invading meningiomas (7 with skull base and 5 with convexity meningiomas) who had undergone surgery with the assistance of 5-ALA fluorescence and neuronavigation between July 2012 and March 2013 at the Department of Neurosurgery of Padua were retrospectively analyzed. To evaluate the sensitivity and specificity of 5-ALA fluorescence in detecting meningioma tissue, a pathologist analyzed 98 surgical bone samples under blue light, according to different fluorescence patterns. Magnetic resonance images and CT scans were obtained pre- and postoperatively to determine the extent of bone invasion resection.
  
  
  RESULTS
  The rate of 5-ALA-induced fluorescence of both tumor and bone invasion was 100%. Based on the pathological examination of bone specimens, 5-ALA presented a sensitivity of 89.06% (95% CI 81.41%-96.71%) and a specificity of 100% in detecting meningioma bone invasion, while the positive and negative predictive values were 100% and 82.93% (95% CI 71.41%-94.45%), respectively. At the postoperative stage, MRI did not detect cases of meningioma bone invasion, whereas CT scans revealed residual hyperostosis in 2 cases.
  
  
  CONCLUSIONS
  In summary, 5-ALA fluorescence represents a suitable and reliable technique for identifying and removing bone infiltration by meningiomas. However, further studies are needed to prove the clinical consequences of this promising technique in a larger population.
authors.affiliation: Department of Neurosurgery, Padua University Hospital;
authors.forename: Alessandro
authors.initials: A
authors.lastname: Della Puppa
authors.forename: Oriela
authors.initials: O
authors.lastname: Rustemi
authors.forename: Giorgio
authors.initials: G
authors.lastname: Gioffrè
authors.forename: Irene
authors.initials: I
authors.lastname: Troncon
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Lombardi
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Rolma
authors.forename: Massimo
authors.initials: M
authors.lastname: Sergi
authors.forename: Marina
authors.initials: M
authors.lastname: Munari
authors.forename: Diego
authors.initials: D
authors.lastname: Cecchin
authors.forename: Marina Paola
authors.initials: MP
authors.lastname: Gardiman
authors.forename: Renato
authors.initials: R
authors.lastname: Scienza
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000622:Aminolevulinic Acid; D005260:Female; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000473:pathology / Q000601:surgery*; D008579:Meningioma / Q000556:secondary / Q000601:surgery*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D019292:Skull Base Neoplasms / Q000175:diagnosis* / Q000556:secondary / Q000601:surgery
chemical_list: D000622:Aminolevulinic Acid