title: A prospective study on contrast-enhanced magnetic resonance imaging of testicular lesions: distinctive features of Leydig cell tumours.
abstract: OBJECTIVE
  Up to 20 % of incidentally found testicular lesions are benign Leydig cell tumours (LCTs). This study evaluates the role of contrast-enhanced magnetic resonance imaging (MRI) in the identification of LCTs in a large prospective cohort study.
  
  
  METHODS
  We enrolled 44 consecutive patients with at least one solid non-palpable testicular lesion who underwent scrotal MRI. Margins of the lesions, signal intensity and pattern of wash-in and wash-out were analysed by two radiologists. The frequency distribution of malignant and benign MRI features in the different groups was compared by using the chi-squared or Fisher's exact test. Sensitivity, specificity, positive and negative predictive value, and diagnostic accuracy were calculated.
  
  
  RESULTS
  The sensitivity of scrotal MRI to diagnose LCTs was 89.47 % with 95.65 % specificity; sensitivity for malignant lesions was 95.65 % with 80.95 % specificity. A markedly hypointense signal on T2-WI, rapid and marked wash-in followed by a prolonged washout were distinctive features significantly associated with LCTs. Malignant lesions were significantly associated with blurred margins, weak hypointense signal on T2-WI ,and weak and progressive wash-in. The overall diagnostic accuracy was 93 %.
  
  
  CONCLUSIONS
  LCTs have distinctive contrast-enhanced MRI features that allow the differential diagnosis of incidental testicular lesions.
  
  
  CONCLUSIONS
  • MRI is able to characterize testicular lesions suggesting a specific diagnosis. • Rapid and marked wash-in is a common feature of Leydig cell tumours. • Markedly hypointense T2-WI signal is significantly correlated with benign lesions. • Blurred margins and weak hypointense T2-WI signal are correlated with malignant tumours. • Weak and progressive wash-in features are present in 85 % of seminomatous lesions.
authors.affiliation: Department of Radiology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy. lucia.manganaro@uniroma1.it.
authors.forename: Lucia
authors.initials: L
authors.lastname: Manganaro
authors.affiliation: Department of Radiology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy.
authors.forename: Valeria
authors.initials: V
authors.lastname: Vinci
authors.affiliation: Department of Experimental Medicine, Sapienza University of Rome, Viale del Policlinico 155, 00161, Rome, Italy.
authors.forename: Carlotta
authors.initials: C
authors.lastname: Pozza
authors.affiliation: Department of Radiology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy.
authors.forename: Matteo
authors.initials: M
authors.lastname: Saldari
authors.affiliation: Department of Experimental Medicine, Sapienza University of Rome, Viale del Policlinico 155, 00161, Rome, Italy.
authors.forename: Daniele
authors.initials: D
authors.lastname: Gianfrilli
authors.affiliation: Department of Experimental Medicine, Sapienza University of Rome, Viale del Policlinico 155, 00161, Rome, Italy.
authors.forename: Riccardo
authors.initials: R
authors.lastname: Pofi
authors.affiliation: Department of Radiology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy.
authors.forename: Silvia
authors.initials: S
authors.lastname: Bernardo
authors.affiliation: Department of Radiology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy.
authors.forename: Vito
authors.initials: V
authors.lastname: Cantisani
authors.affiliation: Department of Experimental Medicine, Sapienza University of Rome, Viale del Policlinico 155, 00161, Rome, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Lenzi
authors.affiliation: Department of Surgical and Biomedical Sciences, Division of Radiology 2, Perugia University, S. Maria della Misericordia Hospital, S. Andrea delle Fratte, 06156, Perugia, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Scialpi
authors.affiliation: Department of Radiology, Sapienza University of Rome, Viale Regina Elena 324, 00161, Rome, Italy.
authors.forename: Carlo
authors.initials: C
authors.lastname: Catalano
authors.affiliation: Department of Experimental Medicine, Sapienza University of Rome, Viale del Policlinico 155, 00161, Rome, Italy.
authors.forename: Andrea M
authors.initials: AM
authors.lastname: Isidori
mesh_terms: D000328:Adult; D015331:Cohort Studies; D003287:Contrast Media; D003937:Diagnosis, Differential; D006801:Humans; D007089:Image Enhancement; D007984:Leydig Cell Tumor / Q000473:pathology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013736:Testicular Neoplasms / Q000473:pathology*; D013737:Testis / Q000473:pathology
chemical_list: D003287:Contrast Media
keywords: Contrast enhanced MRI; Leydig cell tumours; Magnetic resonance imaging; Seminoma; Testicular cancer