Contrast-enhanced Ultrasound Combined With Elastography for the Evaluation of Muscle-invasive Bladder Cancer in Rats

Abstract

Objectives: By comparing with the control group, we evaluated the usefulness of contrast-enhanced ultrasound (CEUS) combined with elastography for the assessment of muscle invasion by bladder cancer (MIBC) in a Sprague-Dawley (SD) rat model.

Methods: In the experimental group, 40 SD rats developed in situ bladder cancer (BLCA) in response to N-methyl-N-nitrosourea treatment, whereas 40 SD rats were included in the control group for comparison. We compared PI, E_mean , microvessel density (MVD), and collagen fiber content (CFC) between the two groups. In the experimental group, Bland-Altman test was used to assess the relationships between various parameters. The largest Youden value was used as the cut-off point, and binomial logistic regression analysis was performed to analyze the PI and E_mean . Receiver operating characteristic (ROC) curve analysis was performed to determine the diagnostic power of parameters, individually and in combination.

Results: The PI, E_mean , MVD, and CFC were significantly lower in the control group than in the experimental group (P < .05). The PI, E_mean , MVD, and CFC were significantly higher for MIBC than for non-muscle-invasive bladder cancer (P < .05). There were significant correlations between PI and MVD, and between E_mean and CFC. The diagnostic efficiency analysis showed PI had the highest sensitivity, CFC had the highest specificity, and PI + E_mean had the highest diagnostic efficacy.

Conclusion: CEUS and elastography can distinguish lesions from normal tissue. PI, MVD, E_mean , and CFC were useful for the detection of BLCA myometrial invasion. The comprehensive utilization of PI and E_mean improved diagnostic accuracy and have clinical application.

Keywords: bladder cancer; collagen fibers; contrast-enhanced ultrasound; elastography; microvessel density; muscle invasion.