Radiofrequency ablation of renal tumours: diagnostic accuracy of contrast-enhanced ultrasound for early detection of residual tumour.
OBJECTIVE
To evaluate the diagnostic accuracy of contrast-enhanced ultrasound (CEUS) in the early detection of residual tumour after radiofrequency ablation (RFA) of renal tumours.


METHODS
Patients referred to our institution for RFA of renal tumours prospectively underwent CEUS and computed tomography (CT) or magnetic resonance imaging (MRI) before, within 1 day and 6 weeks after treatment. Identification of residual tumour was assessed by three blinded radiologists. Reference standard was CT/MRI performed at least 1 year after RFA.


RESULTS
A total of 66 renal tumours in 43 patients (median age 62 years; range 44-71.5) were studied. Inter-reader agreement (kappa value) was 0.84 for CEUS. Prevalence of residual disease was 19%. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV), respectively, were as follows: 64% [confidence interval (CI) 39-84], 98% [CI 91-100], 82% [CI 52-95] and 92% [CI 83-97] on 24-h CEUS; 79% [CI 52-92], 100% [CI 94-100], 100% [CI 74-100] and 95% [CI 87-100] on 6-week CEUS; 79% [CI 52-92], 95% [CI 86-98], 79% [CI 52-92] and 95% [CI 86-98] on 24-h CT/MRI; and 100% [CI 72-100], 98% [CI 90-100], 91% [CI 62-98] and 100% [CI 93-100] on 6-week CT/MRI.


CONCLUSIONS
CEUS has high specificity for the early diagnosis of residual tumour after renal RFA.
Hoeffel
Christine
C
CHU de Reims, Hôpital Robert Debré, Pôle d'imagerie, Service de Radiologie, Reims, France. choeffel-fornes@chu-reims.fr
Pousset
Maud
M
Timsit
Marc-Olivier
MO
Elie
Caroline
C
Méjean
Arnaud
A
Merran
Samuel
S
Tranquart
François
F
Khairoune
Ahmed
A
Joly
Dominique
D
Richard
Stéphane
S
Hélénon
Olivier
O
Correas
Jean-Michel
JM
D000328:Adult; D000368:Aged; D017115:Catheter Ablation / Q000379:methods*; D003287:Contrast Media; D042241:Early Diagnosis; D005260:Female; D006498:Hepatectomy / Q000379:methods; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007680:Kidney Neoplasms / Q000000981:diagnostic imaging* / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000000981:diagnostic imaging / Q000517:prevention & control*; D018365:Neoplasm, Residual / Q000000981:diagnostic imaging*; D010743:Phospholipids; D011379:Prognosis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D013459:Sulfur Hexafluoride; D016896:Treatment Outcome; D014463:Ultrasonography / Q000379:methods
D003287:Contrast Media; D010743:Phospholipids; C420843:contrast agent BR1; D013459:Sulfur Hexafluoride