title: Clinical performance of 2 dedicated PET scanners for breast imaging: initial evaluation.
abstract: The purpose of this study was to investigate the diagnostic performance of 2 newly developed dedicated breast PET scanners in patients with known or suspected breast cancer.
  
  
  METHODS
  Two types of scanner were evaluated, an O-shaped scanner and a C-shaped scanner. The O scanner was designed for imaging patients who were prone, and the C scanner was designed for those patients positioned leaning forward. Sixty-nine women with known or suspected breast carcinoma (80 lesions: 72 invasive carcinomas, 4 noninvasive carcinomas [ductal carcinoma in situ, or DCIS], 1 case of adenomatous ductal hyperplasia, and 3 benign lesions) were enrolled in this study. All patients underwent a conventional whole-body PET/CT scan, followed by breast scanning using both dedicated devices. The diagnostic performance of each scanner was assessed.
  
  
  RESULTS
  The maximal diameter of invasive tumors ranged from 4 to 112 mm, with an average of 26 mm. With the O scanner, 62 of 76 malignant lesions (including 3 DCIS) were detected, 5 lesions were not detected, and the remaining 9 lesions were outside the field of view. With the C scanner, 63 of 76 malignant lesions (including 2 DCIS) were detected, 7 lesions were not detected, and the remaining 6 lesions were outside the field of view. The lesion-based sensitivities of the O and C scanners were 82% (62/76) and 83% (63/76), respectively; sensitivities excluding lesions outside the field of view were 93% (62/67) and 90% (63/70), respectively. The sensitivity of conventional PET/CT was 92% (70/76). All lesions outside the field of view were close to the chest wall. The breast-based specificities of the O, C, and conventional scanners were 98% (48/49), 98% (56/57), and 100% (70/70), respectively.
  
  
  CONCLUSIONS
  Our preliminary study indicates that both dedicated breast PET scanners are clinically feasible and yield reasonably high sensitivity. More detailed information was obtained with these scanners than with the conventional scanner.
authors.affiliation: Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan.
authors.forename: Mami
authors.initials: M
authors.lastname: Iima
authors.forename: Yuji
authors.initials: Y
authors.lastname: Nakamoto
authors.forename: Shotaro
authors.initials: S
authors.lastname: Kanao
authors.forename: Tomoharu
authors.initials: T
authors.lastname: Sugie
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ueno
authors.forename: Mayumi
authors.initials: M
authors.lastname: Kawada
authors.forename: Yoshiki
authors.initials: Y
authors.lastname: Mikami
authors.forename: Masakazu
authors.initials: M
authors.lastname: Toi
authors.forename: Kaori
authors.initials: K
authors.lastname: Togashi
mesh_terms: D001940:Breast / Q000000981:diagnostic imaging*; D001943:Breast Neoplasms / Q000000981:diagnostic imaging*; D005260:Female; D006801:Humans; D049268:Positron-Emission Tomography / Q000295:instrumentation*