title: Three-minute SPECT/CT is sufficient for the assessment of bone metastasis as add-on to planar bone scintigraphy: prospective head-to-head comparison to 11-min SPECT/CT.
abstract: BACKGROUND
  The aim of this study is to assess whether ultra-fast acquisition SPECT/CT (UF-SPECT/CT) can replace standard SPECT/CT (std-SPECT/CT) as "add-on" to whole-body bone scintigraphy (WB-BS) for the investigation of bone metastases. Consecutive cancer patients referred for WB-BS who underwent SPECT/CT in addition to WB-BS were included. Std-SPECT, UF-SPECT, and low-dose CT were performed (std-SPECT: matrix 128 × 128, zoom factor 1, 20 s/view, 32 views; UF-SPECT: identical parameters except for 10 s/view and 16 views, reducing the acquisition time from 11 to 3 min). A consensus diagnosis was reached by two observers for each set of images (WB-BS + standard SPECT/CT or WB-BS + UF-SPECT/CT) using a three-category evaluation scale: M0: no bone metastases; M1: bone metastases; and Me: equivocal findings.
  
  
  RESULTS
  Among the 104 included patients, most presented with prostate cancer (n = 71) or breast cancer (n = 28). Using WB-BS + std-SPECT/CT, 71 (68%) patients were classified as M0, 19 (18%) as M1, and 14 (14%) as Me. Excellent agreement was observed between WB-BS + std-SPECT/CT and WB-BS + UF-SPECT/CT using the three-category scale: kappa = 0.91 (95% CI 0.84-0.97). No difference in observer agreement between cancer types was detected. SPECT/CT provided a definitive classification in 90 of 104 cases in which WB-BS was not entirely diagnostic.
  
  
  CONCLUSIONS
  To investigate potential bone metastases, UF-SPECT/CT can be conducted as add-on to WB-BS to notably reduce the SPECT acquisition time without compromising diagnostic confidence.
authors.affiliation: Department of Nuclear Medicine and Clinical Cancer Research Center, Aalborg University Hospital, Aalborg, Denmark. h.zacho@rn.dk.|Department of Nuclear Medicine, Aalborg University Hospital, Hobrovej 18-22, Postboks 365, 9100, Aalborg, Denmark. h.zacho@rn.dk.
authors.forename: Helle D
authors.identifier: http://orcid.org/0000-0001-9089-288X
authors.initials: HD
authors.lastname: Zacho
authors.affiliation: Department of Health Science and Technology, Center for Neuroplasticity and Pain, Aalborg University, Aalborg, Denmark.|Centro de Investigaciones y Transferencia de Entre Ríos, CONICET-UNER, Entre Ríos, Argentina.
authors.forename: José A Biurrun
authors.initials: JAB
authors.lastname: Manresa
authors.affiliation: Department of Nuclear Medicine and Clinical Cancer Research Center, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Ramune
authors.initials: R
authors.lastname: Aleksyniene
authors.affiliation: Dept. of Nuclear Medicine, Regional Hospital West Jutland, Herning, Denmark.
authors.forename: June A
authors.initials: JA
authors.lastname: Ejlersen
authors.affiliation: Dept. of Nuclear Medicine, Regional Hospital West Jutland, Herning, Denmark.
authors.forename: Joan
authors.initials: J
authors.lastname: Fledelius
authors.affiliation: Department of Nuclear Medicine and Clinical Cancer Research Center, Aalborg University Hospital, Aalborg, Denmark.
authors.forename: Henrik
authors.initials: H
authors.lastname: Bertelsen
authors.affiliation: Department of Nuclear Medicine and Clinical Cancer Research Center, Aalborg University Hospital, Aalborg, Denmark.|Department of Nuclear Medicine, Aalborg University Hospital, Hobrovej 18-22, Postboks 365, 9100, Aalborg, Denmark.
authors.forename: Lars J
authors.initials: LJ
authors.lastname: Petersen
keywords: Agreement; Bone metastases; Bone scintigraphy; Fast acquisition; SPECT/CT