title: PET-Probe: Evaluation of Technical Performance and Clinical Utility of a Handheld High-Energy Gamma Probe in Oncologic Surgery.
abstract: Positron emission tomography (PET) has become an invaluable part of patient evaluation in surgical oncology. PET is less than optimal for detecting lesions <1 cm, and the intraoperative localization of small PET-positive lesions can be challenging as a result of difficulties in surgical exposure. We undertook this investigation to assess the utility of a handheld high-energy gamma probe (PET-Probe) for intraoperative identification of18F-deoxyglucose (FDG)-avid tumors.
  
  
  
  Forty patients underwent a diagnostic whole-body FDG-PET scan for consideration for surgical exploration and resection. Before surgery, all patients received an intravenous injection of 7 to 10 mCi of FDG. At surgery, the PET-Probe was used to determine absolute counts per second at the known tumor site(s) demonstrated by whole-body PET and at adjacent normal tissue (at least 4 cm away from tumor-bearing sites). Tumor-to-background ratios were calculated.
  
  
  
  Thirty-two patients (80%) underwent PET-Probe-guided surgery with therapeutic intent in a recurrent or metastatic disease setting. Eight patients underwent surgery for diagnostic exploration. Anatomical locations of the PET-identified lesions were neck and supraclavicular (n = 8), axilla (n = 5), groin and deep iliac (n = 4), trunk and extremity soft tissue (n = 3), abdominal and retroperitoneal (n = 19), and lung (n = 2). PET-Probe detected all PET-positive lesions. The PET-Probe was instrumental in localization of lesions in 15 patients that were not immediately apparent by surgical exploration.
  
  
  
  The PET-Probe identified all lesions demonstrated by PET scanning and, in selected cases, was useful in localizing FDG-avid disease not seen with conventional PET scanning.
authors.affiliation: Center for Cancer Care at Goshen Health System, 200 High Park Avenue, Goshen, Indiana, USA, 46526. sgulec@goshenhealth.com.
authors.forename: Seza A
authors.initials: SA
authors.lastname: Gulec
authors.affiliation: IntraMedical Imaging LLC, 12340 Santa Monica Blv. Suite 227, Los Angeles, CA, 90025, California, USA.
authors.forename: Farhad
authors.initials: F
authors.lastname: Daghighian
authors.affiliation: John Wayne Cancer Institute, 2200 Santa Monica Blv, Santa Monica, CA, 90404, California, USA.
authors.forename: Richard
authors.initials: R
authors.lastname: Essner
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D019788:Fluorodeoxyglucose F18; D005720:Gamma Rays; D006801:Humans; D007432:Intraoperative Period; D008297:Male; D008875:Middle Aged; D009362:Neoplasm Metastasis; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging* / Q000601:surgery*; D009369:Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology / Q000601:surgery*; D049268:Positron-Emission Tomography; D011446:Prospective Studies; D011874:Radiometry / Q000295:instrumentation / Q000379:methods; D019275:Radiopharmaceuticals; D055815:Young Adult
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18