Adrenal Washout Calculation - CT



Washout measurements may have significantly reduced specificity in patients with renal cell carcinoma (RCC) and hepatocellular carcinoma (HCC).

     Choi YA, Kim CK, Park BK, et al. Evaluation of adrenal metastases from renal cell carcinoma and hepatocellular carcinoma: use of delayed contrast-enhanced CT. Radiology 2013; 266:514-520

Precontrast attenuation of more than 43 HU in a noncalcified, nonhemorrhagic lesion is suspicious for malignancy, regardless of washout characteristics.

     Blake MA, Kalra MK, Sweeney AT, et al. Distinguishing benign from malignant adrenal masses: multi-detector row CT protocol with 10-minute delay. Radiology 2005; 238:578-585

In a study of 61 adrenal masses with noncontrast attenuation at least 10 HU, sensitivity and specificity of absolute washout for adenomas was 86% and 92%, and sensitivity and specificity of relative washout was 82% and 92%.

     Caoili EM, Korobkin M, Francis IR, et al. Adrenal masses: characterization with combined unenhanced and delayed enhanced CT. Radiology 2002; 222:629-633

Disclaimer: The author makes no claims of the accuracy of the information contained herein; this information is for educational purposes only and is not a substitute for clinical judgment.