title: Delineation of small mobile tumours with FDG-PET/CT in comparison to pathology in breast cancer patients.
abstract: OBJECTIVE
  Various segmentation methods for 18F-fluoro-2-deoxy-d-glucose (FDG) positron emission tomography/computed tomography (PET/CT) images were correlated with pathological volume in breast cancer patients as a model of small mobile tumours.
  
  
  METHODS
  Thirty women with T2-T3/M0 breast invasive ductal carcinoma (IDC) were included prospectively. A FDG-PET/CT was acquired 4 ± 3d before surgery in prone and supine positions, with/without respiratory gating. The segmentation methods were as follows: manual (Vm), relative (Vt%) and adaptive (Va) standard uptake value (SUV) threshold and semi-automatic on CT (Vct). Pathological volumes (Vpath) were measured for 26 lesions.
  
  
  RESULTS
  The mean (±SD) Vpath was 4.1 ± 2.9 mL, and the lesion displacements were 3.9 ± 2.8 mm (median value: 3 mm). The delineated VOIs did not vary with the acquisition position nor with respiration, regardless of the segmentation method. The Vm, Va, Vct and Vt% methods, except Vt30%, were correlated with Vpath (0.5<r<0.8). The Vt50% and Vm were the most accurate methods (mean±SD: 0.0 ± 1.6 mL and +0.6 ± 1.8 mL, respectively), followed by the Vct method.
  
  
  CONCLUSIONS
  When compared with pathology, small lesions (diameter <50mm) with limited respiratory displacement (i.e., breast or apical lung lesions) are best delineated on FDG-PET/CT using a 50% SUVmax threshold. The acquisition position and respiratory gating did not modify the delineated volumes.
authors.affiliation: Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rouen, France; Rouen University Hospital, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: sebastien.hapdey@chb.unicancer.fr.
authors.forename: Sébastien
authors.initials: S
authors.lastname: Hapdey
authors.affiliation: Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rouen, France; Rouen University Hospital, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: agathe.edet-sanson@chb.unicancer.fr.
authors.forename: Agathe
authors.initials: A
authors.lastname: Edet-Sanson
authors.affiliation: Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rouen, France; Rouen University Hospital, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: pierrick.gouel@chb.unicancer.fr.
authors.forename: Pierrick
authors.initials: P
authors.lastname: Gouel
authors.affiliation: Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rouen, France; Rouen University Hospital, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: benoit.martin@etu.univ-rouen.fr.
authors.forename: Benoît
authors.initials: B
authors.lastname: Martin
authors.affiliation: Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rouen, France; Rouen University Hospital, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: romain.modzelewski@chb.unicancer.fr.
authors.forename: Romain
authors.initials: R
authors.lastname: Modzelewski
authors.affiliation: Department of Surgery, Henri Becquerel Cancer Centre, Rouen, France. Electronic address: marc.baron@chb.unicancer.fr.
authors.forename: Marc
authors.initials: M
authors.lastname: Baron
authors.affiliation: Department of Pathology, Henri Becquerel Cancer Centre, Rouen, France. Electronic address: anca.berghian@chb.unicancer.fr.
authors.forename: Anca
authors.initials: A
authors.lastname: Berghian
authors.affiliation: Department of Surgery, Henri Becquerel Cancer Centre, Rouen, France. Electronic address: frederique.forestier-lebreton@chb.unicancer.fr.
authors.forename: Frédérique
authors.initials: F
authors.lastname: Forestier-Lebreton
authors.affiliation: Department of Surgery, Henri Becquerel Cancer Centre, Rouen, France. Electronic address: dragos.georgescu@chb.unicancer.fr.
authors.forename: Dragos
authors.initials: D
authors.lastname: Georgescu
authors.affiliation: Department of Pathology, Henri Becquerel Cancer Centre, Rouen, France. Electronic address: jean-michel.picquenot@chb.unicancer.fr.
authors.forename: Jean-Michel
authors.initials: JM
authors.lastname: Picquenot
authors.affiliation: Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rouen, France; Rouen University Hospital, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: isabelle.gardin@chb.unicancer.fr.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Gardin
authors.affiliation: Department of Radiotherapy, Henri Becquerel Cancer Centre, Rouen, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: bernard.dubray@chb.unicancer.fr.
authors.forename: Bernard
authors.initials: B
authors.lastname: Dubray
authors.affiliation: Department of Nuclear Medicine, Henri Becquerel Cancer Centre, Rouen, France; Rouen University Hospital, France; QuantIF - LITIS [UPRES EA 4108], Rouen, France. Electronic address: pierre.vera@chb.unicancer.fr.
authors.forename: Pierre
authors.initials: P
authors.lastname: Vera
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001940:Breast / Q000000981:diagnostic imaging / Q000473:pathology; D001943:Breast Neoplasms / Q000175:diagnosis* / Q000473:pathology; D018270:Carcinoma, Ductal, Breast / Q000175:diagnosis* / Q000473:pathology; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008327:Mammography / Q000379:methods; D008875:Middle Aged; D064847:Multimodal Imaging / Q000379:methods; D049268:Positron-Emission Tomography / Q000379:methods*; D011446:Prospective Studies; D019275:Radiopharmaceuticals; D014057:Tomography, X-Ray Computed / Q000379:methods*; D047368:Tumor Burden
chemical_list: D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18
keywords: Breast cancer; FDG; Pathology; Respiratory gated PET; Tumour delineation; Tumour volume