title: Bromophenol blue staining of tumors in a rat glioma model.
abstract: OBJECTIVE
  For patients with gliomas, decreasing the tumor burden with macroscopic surgical resection may affect quality of life, time to tumor progression, and survival. Injection of bromophenol blue (BPB) may enhance intraoperative visualization of an infiltrating tumor and its margins and improve the extent of resection. In this study, we investigated the uptake of BPB in experimental rat brain tumors.
  
  
  METHODS
  We first conducted a toxicity study with bolus intravenous injections of 5, 60, and 360 mg/kg doses of BPB in nontumor-bearing Fischer 344 rats. No adverse effects were observed in any of the animals during the 60 day observation period. We then injected 9L tumor cells intracerebrally into Fischer 344 rats and approximately 2 weeks later, administered a bolus intravenous injection of 5 to 360 mg/kg BPB. Fifteen minutes after BPB injection, we sacrificed the animals and removed their brains. In a subsequent study, we injected 180 mg/kg BPB and sacrificed animals at several time points to monitor tumor staining over time.
  
  
  RESULTS
  The stain was clearly visible and localized to the tumor for all BPB concentrations 60 mg/kg or greater, and in an additional experiment, we found that tumor staining persisted for at least 8 hours after BPB injection.
  
  
  CONCLUSIONS
  We conclude that BPB helped visualize experimental tumors at time points from a few minutes to several hours after injection. Because BPB also proved to be nontoxic to the animals at effective concentrations, we believe the compound may be potentially useful in helping neurosurgeons visualize brain tumors in humans.
authors.affiliation: Department of Neurological Surgery, Brain Tumor Research Center, University of California, San Francisco, California, USA.
authors.forename: Tomoko
authors.initials: T
authors.lastname: Ozawa
authors.forename: Gavin W
authors.initials: GW
authors.lastname: Britz
authors.forename: David H
authors.initials: DH
authors.lastname: Kinder
authors.forename: Alexander M
authors.initials: AM
authors.lastname: Spence
authors.forename: Scott
authors.initials: S
authors.lastname: VandenBerg
authors.forename: Kathleen R
authors.initials: KR
authors.lastname: Lamborn
authors.forename: Dennis F
authors.initials: DF
authors.lastname: Deen
authors.forename: Mitchel S
authors.initials: MS
authors.lastname: Berger
mesh_terms: D000818:Animals; D001932:Brain Neoplasms / Q000175:diagnosis*; D001978:Bromphenol Blue / Q000008:administration & dosage; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005910:Glioma / Q000175:diagnosis*; D007202:Indicators and Reagents / Q000008:administration & dosage; D008297:Male; D009368:Neoplasm Transplantation / Q000379:methods; D009374:Neoplasms, Experimental / Q000175:diagnosis; D051381:Rats; D011916:Rats, Inbred F344; D013997:Time Factors
chemical_list: D007202:Indicators and Reagents; D001978:Bromphenol Blue