Contrast‐enhanced ultrasound (CEUS) of benign and malignant renal tumors: Distinguishing CEUS features differ with tumor size

Abstract

Background Contrast‐enhanced ultrasound (CEUS) is now a guideline‐recommended strategy for diagnosing renal lesions. Tumor size is related to the risk of the treatment and prognosis in renal tumors. Thus, we aim to analyze the CEUS features of solid renal tumors in relation to tumor size. Methods The CEUS appearance of 156 pathologically diagnosed solid renal tumors were retrospectively analyzed. Three groups were stratified according to the tumor size (≤2 cm [group I], 2.1–4 cm [group II] and 4.1–7 cm [group III]). For each group, the features of wash‐in type, enhancement degree, enhancement homogeneity, and the presence of a pseudocapsule sign were compared between benign and malignant tumors. Results All 156 included lesions were detected by CEUS. The proportion of benign tumors in three size groups was 37.1%, 19.4%, and 20.4%, respectively. The proportion of malignant tumors was highest (80.6%) in group II, followed by group III (79.6%) and group I (62.9%). In group I, malignant and benign tumors differed significantly in the presence of a pseudocapsule sign ( p = 0.015) and homogeneity ( p = 0.007). In group II, the degree of enhancement differed ( p = 0.02) between tumor types. In group III, the two tumor types differed in both the wash‐in pattern ( p = 0.015) and enhancement degree ( p = 0.024). The weighted and Cohen's kappa values for the concordance between inter‐observer agreement ranged from 0.31 (95% CI: 0.36–0.57) to 0.90 (95% CI: 0.77–1.00). Conclusions CEUS features of malignant and benign renal tumors change along with the tumor size. The use of CEUS features in the diagnosis of benign and malignant tumors requires consideration of tumor size.

Clinical diagnostic value of contrast-enhanced ultrasound combined with microflow imaging in benign and malignant renal tumors: A retrospective cohort study

“…Subsequently, we compared and analyzed the differences in CUS and CEUS characteristics between benign and malignant tumors. Benign and malignant renal tumors in this study mostly presented as well-circumscribed round-like lesions, consistent with previous findings [17]. This may be related to the growth pattern of renal tumors.…”

“…As a low-cost and well-tolerated imaging method, CEUS can dynamically display microcirculatory perfusion and tumor vasculature in real time, and its value in differentiating between benign and malignant renal tumors has been widely recognized [16,17]. However, the specificity of CEUS in diagnosing benign and malignant renal tumors is relatively low due to the overlapping ultrasound findings across different pathological types, which cannot be judged solely from the contrast-enhanced mode [17]. In the CEUS mode, the hyperenhancement ring around the lesion can reflect the capillary condition in the pseudocapsule around the renal tumor with high specificity [8,18].…”

Qualitative and quantitative assessment of non-clear cell renal cell carcinoma using contrast-enhanced ultrasound

“…However, multivariate Logistic regression analysis showed that the pseudocapsule sign is an independent predictor of RCC [ 16 ]. Zhu et al [ 17 ] reported a significant difference in the incidence of CEUS pseudocapsule visualization among RCC patients across various tumor-size subgroups. Notably, the highest pseudocapsule visualization rate was observed in medium-sized tumors (with a diameter of 2–4 cm), reaching 79.3%.…”

Characteristics of high frame frequency contrast-enhanced ultrasound in renal tumors

“…A previous study [ 27 ] suggested that the contrast-enhanced ultrasonographic findings of RCC may be affected by mass size. Jun Jiang [ 28 ] reported that there was no statistical significance between the peak intensity of CEUS of ccRCC and tumor size, but there was a good correlation between enhanced homogeneity and the frequency of pseudocapsule and tumor size.…”