title: Successful diagnosis of orthotopic rat superficial bladder tumor model by ultrathin cystoscopy.
abstract: OBJECTIVE
  In the orthotopic animal bladder tumor model noninvasive evaluation of the tumor establishment and the therapeutic effect has been difficult. To our knowledge we present the first diagnosis of orthotopic rat superficial bladder tumor model by ultrathin cystoscopy.
  
  
  METHODS
  The established AY-27 rat bladder carcinoma cell line was transplanted orthotopically into 22 female Fischer F344 rats. A cell suspension containing 4 x 10 AY-27 cells was instilled into the bladder, which had been conditioned with mild acid washing. To evaluate tumor growth serial cystoscopy was performed via the urethra with an ultrathin endoscope (diameter 0.75 mm.) 5 to 14 days after tumor cell inoculation. At intervals after cystoscopic tumor detection the rats were sacrificed for autopsy and histological examination.
  
  
  RESULTS
  In all 22 rats the orthotopic bladder tumor was established 7 to 10 days after tumor cell implantation and in most it was superficial. Cystoscopy permitted inspection of the urethra and whole bladder surface. We detected all tumors as broad based papillary mass (minimal lesion 1 mm. or less) and inspected its detailed appearance and accurate location.
  
  
  CONCLUSIONS
  The orthotopic rat superficial bladder tumor model and the diagnostic procedure by ultrathin cystoscopy would be ideal system for preclinical evaluation of new potential intravesical therapies.
authors.affiliation: Department of Urology, School of Medicine, Faculty of Science and Technology, Keio University, Tokyo, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Asanuma
authors.forename: Tsunenori
authors.initials: T
authors.lastname: Arai
authors.forename: Kenji
authors.initials: K
authors.lastname: Seguchi
authors.forename: Satoko
authors.initials: S
authors.lastname: Kawauchi
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Satoh
authors.forename: Makoto
authors.initials: M
authors.lastname: Kikuchi
authors.forename: Masaru
authors.initials: M
authors.lastname: Murai
mesh_terms: D000818:Animals; D020684:Cystoscopes; D003558:Cystoscopy / Q000379:methods*; D004195:Disease Models, Animal; D004867:Equipment Design; D005260:Female; D009368:Neoplasm Transplantation; D051381:Rats; D011916:Rats, Inbred F344; D001749:Urinary Bladder Neoplasms / Q000175:diagnosis*