Strain elastography in the characterization of renal cell carcinoma and angiomyolipoma.
BACKGROUND
We evaluate the diagnostic performance of strain elastography to differentiate renal cell carcinoma (RCC) from angiomyolipoma (AML).


METHODS
Strain elastography was performed in 65 patients (mean age 55.5 years; range: 32-81) who had renal lesions (24 AMLs and 41 RCCs) prospectively. Lesions were classified according to lesion size and histological subtypes. The strain ratios of the RCCs and AMLs were evaluated by a radiologist. The area under the curve and the cut-off point were used to assess diagnostic performance. Sensitivity, specificity, and positive and negative predictive values were obtained.


RESULTS
In assessing the mean strain ratio, we divided the groups in 3 according to size: (1) <20-mm lesions; (2) 20- to 40-mm lesions; and (3) >40-mm lesions; the respective mean strain ratios were: 1.5 ± 0.5 (range: 0.06-5.92), 2.8 ± 0.4 (range: 0.17-9.92), 2.7 ± 0.3 (range: 0.08-6.15). When RCCs and AMLs were compared, there was a statistically significant difference in the strain ratio among the 3 groups divided per lesion size (p < 0.01). For the strain ratio, the mean ± standard deviation was 1.1 ± 0.1 for AMLs and 3.4 ± 0.3 for RCCs (p < 0.01). When lesion subtypes were compared, there was a statistically significant difference in the strain ratio between the AML and clear cell RCC (p < 0.01).


CONCLUSIONS
For assessing renal lesions, strain elastography and strain ratio values may be useful in differentiating RCCs from AMLs.
Department of Radiology, Necmettin Erbakan University, Meram School of Medicine, Konya, Turkey;
Suat
S
Keskin
Department of Urology, Necmettin Erbakan University, Meram School of Medicine, Konya, Turkey;
Selçuk
S
Güven
Department of Radiology, Konya Training and Research Hospital, Konya, Turkey.
Zeynep
Z
Keskin
Department of Radiology, Necmettin Erbakan University, Meram School of Medicine, Konya, Turkey;
Hüseyin
H
Özbiner
Department of Radiology, Necmettin Erbakan University, Meram School of Medicine, Konya, Turkey;
Ülkü
Ü
Kerimoğlu
Department of Radiology, Necmettin Erbakan University, Meram School of Medicine, Konya, Turkey;
Ahmet
A
Yeşildağ