Can Adrenal Adenomas Be Differentiated From Adrenal Metastases at Single-Phase Contrast-Enhanced CT?

OBJECTIVE. The purpose of this study is to evaluate whether adrenal metastases can be reliably differentiated from adenomas at single-phase contrast-enhanced CT. MATERIALS AND METHODS. Sixty-one consecutive patients from a single-institution lung cancer registry (40 metastases and 36 adenomas) who underwent single-phase contrast-enhanced CT at baseline diagnosis were retrospectively studied by two radiologists (blinded to the diagnoses) who independently evaluated four features previously described in adenomas: smooth margin, rim enhancement, central vein sign (preserved adrenal vein), and homogeneity (using a 5-point Likert scale). A third radiologist measured size and attenuation and performed quantitative texture analysis. Comparisons were performed using chi-square, logistic regression, and ROC analysis. RESULTS. Metastases were larger than adenomas (mean [± SD] 24 ± 11 mm [range, 11–66 mm] vs 19 ± 5 mm [range, 11–34 mm]; p = 0.012), with overlap between groups. Attenuation of metastases and adenomas ...