Diagnostic performance of contrast‐enhanced ultrasonography and magnetic resonance imaging for the assessment of complex renal cysts: A prospective study

Abstract

Objectives: To compare the diagnostic performance of computed tomography, magnetic resonance imaging and contrast enhanced ultrasonography for the assessment of complex renal cysts. Methods: We carried out a prospective single-center study from January 2012 to December 2013. We included patients with Bosniak category 2F or 3 renal cysts found on computed tomography and reviewed by two expert radiologists. Magnetic resonance imaging and contrast-enhanced ultrasonography were then carried out. Patients with a Bosniak ≥3 cyst on magnetic resonance imaging, as well as those upgraded as appearing malignant on contrast-enhanced ultrasonography, were surgically managed. Imaging results were compared with histological data. For patients without surgery, imaging examinations were compared with follow-up data. For each imaging examination, diagnostic performance and Cohen's kappa coefficient were assessed. Results: A total of 47 patients were included. The median follow up was 36 months (range 17-48 months). At initial computed tomography, cysts were classified as Bosniak 2F and Bosniak ≥3 in 34 and 13 patients, respectively. Magnetic resonance imaging found 13 Bosniak ≥3 cysts, and contrast-enhanced ultrasonography upgraded six more patients with cysts that appeared malignant. A total of 19 patients had surgery. Histological analysis reported 14 malignant tumors. No tumor progression was found in followed-up patients. Computed tomography showed poor sensitivity (36%) and specificity (76%; j = 0.11). Magnetic resonance imaging showed 71% sensitivity and 91% specificity (j = 0.64). Contrast-enhanced ultrasonography showed high sensitivity (100%) and specificity (97%), and a negative predictive value at 100% (j = 0.95). Conclusions: The present results suggested that contrast-enhanced ultrasonography could be useful in improving the assessment of complex renal cysts. Indeed, computed tomography accuracy might be limited in this indication requiring further investigations to determine the best treatment strategy.

Comparison of the Diagnostic Performance of Contrast-enhanced Ultrasound with That of Contrast-enhanced Computed Tomography and Contrast-enhanced Magnetic Resonance Imaging in the Evaluation of Renal Masses: A Systematic Review and Meta-analysis

“…In Tian et al's [18] study, RMs with FD by pathology were examined with consensus of both CECT and CEUS. DA, [20] reported a significant difference between CEUS and CEMR and CECT, namely, 0.98 (95% CI 0.96-1.0) versus 0.81 (95% CI 0.68-0.94) and 0.56 (95% CI 0.41-0.71; Table 2).…”

“…In summary, the present results confirm that the diagnostic performance of CEUS is at least comparable with that of not only CECT but also CEMR. Concerning PS and pooled NPV for all subtypes of RMs as well as concerning ROC area in evaluating complex CRMs in one study [20], CEUS showed significantly better diagnostic performance than CEMR.…”

“…Six of the 16 included studies were cohort studies [17][18][19][20][21][22] and 10 were descriptive studies [23][24][25][26][27][28][29][30][31][32]; none were RCTs ( Table 1).…”

“…Comparison of CEUS and CEMR in the diagnosis of benign and malignant RMs produced some interesting results. Defortescu et al [20] compared the diagnostic performance of CEUS and CEMR in 47 complex CRMs. CEUS showed better DA, sensitivity, specificity, ROC area, PPV, and NPV than CEMR.…”

Editorial Comment to Diagnostic performance of contrast‐enhanced ultrasonography and magnetic resonance imaging for the assessment of complex renal cysts: A prospective study

“…Magnetic resonance imaging (MRI) in comparison with CT is significantly more sensitive and insignificantly more specific in distinguishing category IIF from the category III kidney cyst with a documented tendency to falsely upgrade kidney cysts . In this article by Defortescu et al ., the authors showed that CEUS has higher sensitivity and similar specificity compared with MRI, and that the accuracy of CEUS tends to grow with the operator's experience and knowledge of the examination limits . Complex cysts analyzed in this article did not have calcifications, were not localized in the medial aspect of the kidney and no extremely obese patients were examined.…”