title: Hypericin for visualization of high grade gliomas: first clinical experience.
abstract: OBJECTIVE
  We aimed to demonstrate that Hypericin, a component of St. Johns Wort, selectively visualizes malignant gliomas. Hypericin is known as one of the most powerful photosensitizers in nature with excellent fluorescent properties.
  
  
  METHODS
  In five patients with a recurrence of a malignant glioma a newly developed water soluble formulation of hypericin was given intravenously (0.1 mg/kg body weight) 6 h before the surgical procedure. Tumor resection was performed under white light and fluorescence mode. The intensity grade of the tissue fluorescence was categorisized by the surgeon in three grades, highly fluorescent, weakly fluorescent and not fluorescent. In these areas tissue samples were taken and investigated by two blinded independent neuropathologists. Tissue samples were histologically classified differentiating between tumor tissue, tumor necrosis, tissue with scattered tumor cells and normal brain tissue.
  
  
  RESULTS
  In all patients tumor tissue was clearly distinguishable by its typically red fluorescence color from normal brain tissue which was colored blue under a special fluorescent filter. Histological evaluation of the 110 tissue samples showed a specificity of 100% and sensitivity of 91% for one of the two neuropathologists, whereas specificity for second pathologist was 90% and sensitivity 94%. The i.v. application of Hypericin proofed to be safe in all cases and there were no side effects observed.
  
  
  CONCLUSIONS
  Hypericin in its water soluble form is a well tolerated drug. In addition to its high photosensitizing properties hypericin will open up interesting new therapeutic possibilities especially when used in combination with fluorescence detection and simultaneously photodynamic therapy.
authors.affiliation: Klinik für Neurochirurgie, Eberhard Karls Universität Tübingen, Germany. rainer_ritz@hotmail.com
authors.forename: R
authors.initials: R
authors.lastname: Ritz
authors.forename: R
authors.initials: R
authors.lastname: Daniels
authors.forename: S
authors.initials: S
authors.lastname: Noell
authors.forename: G C
authors.initials: GC
authors.lastname: Feigl
authors.forename: V
authors.initials: V
authors.lastname: Schmidt
authors.forename: A
authors.initials: A
authors.lastname: Bornemann
authors.forename: K
authors.initials: K
authors.lastname: Ramina
authors.forename: D
authors.initials: D
authors.lastname: Mayer
authors.forename: K
authors.initials: K
authors.lastname: Dietz
authors.forename: W S L
authors.initials: WS
authors.lastname: Strauss
authors.forename: M
authors.initials: M
authors.lastname: Tatagiba
mesh_terms: D000368:Aged; D000873:Anthracenes; D001932:Brain Neoplasms / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D005260:Female; D005453:Fluorescence; D005910:Glioma / Q000175:diagnosis* / Q000473:pathology / Q000601:surgery; D006801:Humans; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D010569:Perylene / Q000008:administration & dosage / Q000031:analogs & derivatives*; D017319:Photosensitizing Agents / Q000008:administration & dosage; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity
chemical_list: D000873:Anthracenes; D017319:Photosensitizing Agents; D010569:Perylene; C004965:hypericin