title: Perfusion pattern and time of vascularisation with CEUS increase accuracy in differentiating between benign and malignant tumours in 216 musculoskeletal soft tissue masses.
abstract: BACKGROUND
  Musculoskeletal Soft Tissue Tumours (STT) are frequent heterogeneous lesions. Guidelines consider a mass larger than 5 cm and deep with respect to the deep fascia potentially malignant. Contrast Enhanced Ultrasound (CEUS) can detect both vascularity and tumour neoangiogenesis. We hypothesised that perfusion patterns and vascularisation time could improve the accuracy of CEUS in discriminating malignant tumours from benign lesions.
  
  
  METHODS
  216 STT were studied: 40% benign lesions, 60% malignant tumours, 56% in the lower limbs. Seven CEUS perfusion patterns and three types of vascularisation (arterial-venous uptake, absence of uptake) were applied. Accuracy was evaluated by comparing imaging with the histological diagnosis. Univariate and multivariate analysis, Chi-square test and t-test for independent variables were applied; significance was set at p<0.05 level, 95% computed CI.
  
  
  RESULTS
  CEUS pattern 6 (inhomogeneous perfusion), arterial uptake and location in the lower limb were associated with high risk of malignancy. CEUS pattern has PPV 77%, rapidity of vascularisation PPV 69%; location in the limbs is the most sensitive indicator, but NPV 52%, PPV 65%. The combination of CEUS-pattern and vascularisation has 74% PPV, 60% NPV, 70% sensitivity. No correlation with size and location in relation to the deep fascia was found.
  
  
  CONCLUSIONS
  US with CEUS qualitative analysis could be an accurate technique to identify potentially malignant STT, for which second line imaging and biopsy are indicated in Referral Centers. Intense inhomogeneous enhancement with avascular areas and rapid vascularisation time could be useful in discriminating benign from malignant SST, overall when the lower limbs are involved.
authors.affiliation: Department of Imaging, Azienda Ospedaliera Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino, Italy. Electronic address: armanda.demarchi@tiscali.it.
authors.forename: Armanda
authors.initials: A
authors.lastname: De Marchi
authors.affiliation: Department of OrthopaedicOncology and ReconstructiveSurgery, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino, Italy. Electronic address: elena.brach@unito.it.
authors.forename: Elena Brach Del
authors.initials: EBD
authors.lastname: Prever
authors.affiliation: Department of Public health and Paediatrics, University of Turin, Via Santena 5-bis, 10126 Torino, Italy. Electronic address: franco.cavallo@unito.it.
authors.forename: Franco
authors.initials: F
authors.lastname: Cavallo
authors.affiliation: Department of Imaging, Azienda Ospedaliera Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino, Italy. Electronic address: simona.pozza@tin.it.
authors.forename: Simona
authors.initials: S
authors.lastname: Pozza
authors.affiliation: Department of Pathology, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, Regina Margherita Hospital, Piazza Polonia, 10126 Torino, Italy. Electronic address: linaralessandra@libero.it.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Linari
authors.affiliation: Department of DiagnosticImaging and Radiotherapy of the University of Turin, Azienda Ospedaliero-Universitaria Città della Salute e della Scienza di Torino, Via Genova 3, 10126 Torino, Italy. Electronic address: pao.lombardo82@gmail.com.
authors.forename: Paolo
authors.initials: P
authors.lastname: Lombardo
authors.affiliation: Department of Oncology, Gradenigo Hospital, Corso Regina Margherita, 8/10.10153 Torino, Italy. Electronic address: alessandro.comandone@gradenigo.it.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Comandone
authors.affiliation: Department of OrthopaedicOncology and ReconstructiveSurgery, Azienda Ospedaliero Universitaria Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino, Italy. Electronic address: raimondo.piana@libero.it.
authors.forename: Raimondo
authors.initials: R
authors.lastname: Piana
authors.affiliation: Department of Imaging, Azienda Ospedaliera Città della Salute e della Scienza, CTO Hospital, Via Zuretti 29, 10126 Torino, Italy. Electronic address: falettic.@hotmail.it.
authors.forename: Carlo
authors.initials: C
authors.lastname: Faletti
mesh_terms: D003287:Contrast Media; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009140:Musculoskeletal Diseases / Q000150:complications / Q000000981:diagnostic imaging*; D009389:Neovascularization, Pathologic / Q000150:complications / Q000000981:diagnostic imaging*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012983:Soft Tissue Neoplasms / Q000150:complications / Q000000981:diagnostic imaging*; D014463:Ultrasonography
chemical_list: D003287:Contrast Media
keywords: Contrast enhanced ultrasound; Musculoskeletal tumour; Neoangiogenesis; Soft tissue sarcoma; Soft tissue sarcoma guidelines; Soft tissue tumour