Abstract
Purpose To compare the sensitivity and specificity of contrast-enhanced ultrasound (CEUS),
computed tomography (CT) and magnetic resonance imaging (MRI) in the evaluation of
unclear renal lesions to the histopathological outcome.
Materials and methods A total of 255 patients with a single unclear renal mass with initial imaging studies
between 2005 and 2015 were included. Patient ages ranged from 18 to 86 with (mean
age 62 years; SD ± 13). CEUS (255 patients), CT (88 out of 255 patients; 34.5 %) and
MRI (36 out of 255 patients; 14.1 %) were used for determining malignancy or benignancy
and initial findings were correlated with the histopathological outcome.
Results CEUS showed a sensitivity of 99.1 % (95 % confidence interval (CI): 96.7 %, 99.9 %),
a specificity of 80.5 % (95 % CI: 65.1 %, 91.2 %), a positive predictive value (PPV)
of 96.4 % (95 % CI: 93.0 %, 98.4 %) and a negative predictive value (NPV) of 94.3 %
(95 % CI: 80.8 %, 99.3 %). CT showed a sensitivity of 97.1 % (95 % CI: 89.9 %, 99.6 %),
a specificity of 47.4 % (95 % CI: 24.4 %, 71.1 %), a PPV of 87.0 % (95 % CI: 77.4 %,
93.6 %) and a NPV of 81.8 % (95 % CI: 48.2 %, 97.7 %). MRI showed a sensitivity of
96.4 % (95 % CI: 81.7 %, 99.9 %), a specificity of 75.0 % (95 % CI: 34.9 %, 96.8 %),
a PPV of 93.1 % (95 % CI: 77.2 %, 99.2 %) and a NPV of 85.7 % (95 % CI: 42.1 %, 99.6 %).
Out of the 212 malignant lesions a total of 130 clear cell renal carcinomas, 59 papillary
renal cell carcinomas, 7 chromophobe renal cell carcinomas, 4 combined clear cell
and papillary renal cell carcinomas and 12 other malignant lesions, e. g. metastases,
were diagnosed. Out of the 43 benign lesions a total 10 angiomyolipomas, 3 oncocytomas,
8 benign renal cysts and 22 other benign lesions, e. g. renal adenomas were diagnosed.
Using CEUS, 10 lesions were falsely identified as malignant or benign, whereas 8 lesions
were false positive and 2 lesions false negative.
Conclusion CEUS is an useful method which can be additionally used to clinically differentiate
between malignant and benign renal lesions. CEUS shows a comparable sensitivity, specificity,
PPV and NPV to CT and MRI. In daily clinical routine, patients with contraindications
for other imaging modalities can particularly benefit using this method.
Key Points:
Wide availability
Safe applicability in patients with known renal insufficiency or allergies to iodine
or gadolinium
Comparable sensitivity, specificity, PPV and NPV to CT and MRT
May lead to a reduction in interventional radiological or surgical interventions
Citation Format
Marschner CA, Ruebenthaler J, Schwarze V et al. Comparison of computed tomography
(CT), magnetic resonance imaging (MRI) and contrast-enhanced ultrasound (CEUS) in
the evaluation of unclear renal lesions. Fortschr Röntgenstr 2020; 192: 1053 – 1058
Key words incidental renal lesion - magnetic resonance tomography - sensitivity - specificity
- contrast-enhanced ultrasound - computed tomography
