title: Real-time, near-infrared fluorescence imaging with an optimized dye/light source/camera combination for surgical guidance of prostate cancer.
abstract: OBJECTIVE
  The prostate-specific membrane antigen (PSMA) is a surface glycoprotein overexpressed on malignant prostate cells, as well as in the neovasculature of many tumors. Recent efforts to target PSMA for imaging prostate cancer rely on suitably functionalized low-molecular-weight agents. YC-27 is a low-molecular-weight, urea-based agent that enables near-infrared (NIR) imaging of PSMA in vivo.
  
  
  METHODS
  We have developed and validated a laparoscopic imaging system (including an optimized light source, LumiNIR) that is capable of imaging small tumor burdens with minimal background fluorescence in real-time laparoscopic extirpative surgery of small prostate tumor xenografts in murine and porcine models.
  
  
  RESULTS
  In a mouse model, we demonstrate the feasibility of using real-time NIR laparoscopic imaging to detect and surgically remove PSMA-positive xenografts. We then validate the use of our laparoscopic real-time NIR imaging system in a large animal model. Our novel light source, which is optimized for YC-27, is capable of detecting as little as 12.4 pg/mL of the compound (2.48-pg YC-27 in 200-μL agarose). Finally, in a mouse xenograft model, we demonstrate that the use of real-time NIR imaging can reduce positive surgical margins (PSM).
  
  
  CONCLUSIONS
  These data indicate that a NIR-emitting fluorophore targeted to PSMA may allow improved surgical treatment of human prostate cancer, reduce the rate of PSMs, and alleviate the need for adjuvant radiotherapy postoperatively.
authors.affiliation: James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, Maryland.
authors.forename: Brian P
authors.initials: BP
authors.lastname: Neuman
authors.affiliation: James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, Maryland.
authors.forename: John B
authors.initials: JB
authors.lastname: Eifler
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Mark
authors.initials: M
authors.lastname: Castanares
authors.affiliation: James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, Maryland.
authors.forename: Wasim H
authors.initials: WH
authors.lastname: Chowdhury
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Ying
authors.initials: Y
authors.lastname: Chen
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Ronnie C
authors.initials: RC
authors.lastname: Mease
authors.affiliation: James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, Maryland.
authors.forename: Rong
authors.initials: R
authors.lastname: Ma
authors.affiliation: James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, Maryland.
authors.forename: Amarnath
authors.initials: A
authors.lastname: Mukherjee
authors.affiliation: James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, Maryland.
authors.forename: Shawn E
authors.initials: SE
authors.lastname: Lupold
authors.affiliation: The Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins Hospital, Baltimore, Maryland.
authors.forename: Martin G
authors.initials: MG
authors.lastname: Pomper
authors.affiliation: James Buchanan Brady Urological Institute and Department of Urology, The Johns Hopkins School of Medicine, Baltimore, Maryland. RodriguezR32@uthscsa.edu.
authors.forename: Ronald
authors.initials: R
authors.lastname: Rodriguez
mesh_terms: D000818:Animals; D003952:Diagnostic Imaging / Q000379:methods*; D004195:Disease Models, Animal; D005456:Fluorescent Dyes; D064593:Heterografts; D010535:Laparoscopy / Q000379:methods*; D008297:Male; D051379:Mice; D017430:Prostate-Specific Antigen / Q000032:analysis; D011468:Prostatectomy / Q000379:methods*; D011471:Prostatic Neoplasms / Q000601:surgery*; D013055:Spectrophotometry, Infrared; D013552:Swine
chemical_list: D005456:Fluorescent Dyes; D017430:Prostate-Specific Antigen