title: Robotic real-time near infrared targeted fluorescence imaging in a murine model of prostate cancer: a feasibility study.
abstract: OBJECTIVE
  To evaluate the detection of near-infrared fluorescence from prostate tumors stained with a prostate-specific membrane antigen (PSMA)-targeted tracer developed in our institution with a novel robotic imaging system.
  
  
  METHODS
  Prostate cancer cell lines PC3-pip (PSMA positive) and PC3-flu (PSMA negative) were implanted subcutaneously into 6 immunodeficient mice. When tumors reached 5 mm, a PSMA-targeted fluorescent conjugate was injected intravenously. The first 3 mice underwent near-infrared imaging immediately and hourly up to 4 hours after injection to determine the time necessary to obtain peak fluorescence and were killed. The last 3 mice were imaged once preoperatively and were euthanized 120 minutes later. Excision of the tumors was performed by using a novel robotic imaging system to detect near-infrared fluorescence in real time. Specimens were submitted for pathology.
  
  
  RESULTS
  In the first 3 mice, we found 120 minutes as the time needed to observe peak fluorescence from the PSMA-positive tumors. We identified discrete near-infrared fluorescence from 2 of 3 PSMA-positive tumors with the robotic imaging system. Surgical margins were negative for all excised specimens except for one PSMA-negative tumor.
  
  
  CONCLUSIONS
  Real-time near-infrared fluorescence imaging of prostate cancer is feasible with a novel robotic imaging system. Further research is needed to optimize the signal intensity detectable from prostate cancer with our tracer. Toxicologic studies are needed before its clinical use.
authors: Section of Laparoscopic and Robotic Surgery, Glickman Urological and Kidney Institute, Cleveland Clinic, Cleveland, OH 44195, USA.
authors: Humberto
authors: H
authors: Laydner
authors: Steve S
authors: SS
authors: Huang
authors: Warren D
authors: WD
authors: Heston
authors: Riccardo
authors: R
authors: Autorino
authors: Xinning
authors: X
authors: Wang
authors: Kelley M
authors: KM
authors: Harsch
authors: Cristina
authors: C
authors: Magi-Galluzzi
authors: Wahib
authors: W
authors: Isac
authors: Rakesh
authors: R
authors: Khanna
authors: Bo
authors: B
authors: Hu
authors: Pedro
authors: P
authors: Escobar
authors: Sricharan
authors: S
authors: Chalikonda
authors: Pravin K
authors: PK
authors: Rao
authors: Georges-Pascal
authors: GP
authors: Haber
authors: Jihad H
authors: JH
authors: Kaouk
authors: Robert J
authors: RJ
authors: Stein
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D005240:Feasibility Studies; D019085:Fluorescent Antibody Technique, Direct; D005456:Fluorescent Dyes; D043425:Glutamate Carboxypeptidase II / Q000276:immunology; D007259:Infrared Rays; D008297:Male; D008562:Membrane Glycoproteins / Q000276:immunology; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D009368:Neoplasm Transplantation; D061848:Optical Imaging / Q000379:methods*; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000276:immunology / Q000601:surgery; D012371:Robotics
chemical_list: D005456:Fluorescent Dyes; D008562:Membrane Glycoproteins; D043425:Glutamate Carboxypeptidase II; C579805:PSMA protein, mouse