Small Benign Nodules Research Articles

Differentiation of small (≤2cm) hepatocellular carcinomas from small benign nodules in cirrhotic liver on gadoxetic acid-enhanced and diffusion-weighted magnetic resonance images.

To identify imaging characteristics that differentiate small (≤2cm) HCCs from small (≤2cm) benign nodules in cirrhotic liver on gadoxetic acid-enhanced and diffusion-weighted (DW) magnetic resonance (MR) images. On gadoxetic acid-enhanced and DW MR images, we analysed signal intensity of 222 small HCCs and 61 benign nodules (diameter, 0.5-2cm) at each sequence and rim enhancement during portal or equilibrium phases. Univariate and multivariate logistic regression analyses identified predictors of HCC. Combinations of significant MR findings in multivariate analysis were compared with American Association for the Study of Liver Disease (AASLD) practice guidelines. In multivariate analysis, arterial enhancement (adjusted odds ratio [aOR], 8.6), T2 hyperintensity (aOR, 5.8), and hyperintensity on DW images (aOR, 3.8) were significant for differentiating small HCCs from benign nodules (p≤0.004). When two or all three findings were applied as diagnostic criteria for differentiating small HCCs from benign nodules, sensitivity and accuracy were significantly higher compared with AASLD practice guidelines (91% vs. 78% and 89% vs. 81%, respectively; each p<0.0001). On gadoxetic acid-enhanced MR imaging, arterial enhancement and hyperintensity on T2-weighted and DW MR images are helpful for differentiating small HCCs from benign nodules in liver cirrhosis.

The significance of pulmonary nodules detected by CT but not by chest radiography in tumour staging

Computed tomography (CT) is more sensitive than the chest radiograph in the detection of pulmonary metastases, but specificity is lower because CT detects more small benign nodules. This study assessed the significance of pulmonary nodules demonstrated on CT when the chest radiograph was normal. Staging CT scans of 146 patients with extrathoracic primary tumours were reviewed. Thirteen per cent of CT scans showed pulmonary nodules despite a normal chest radiograph. In over 80% of these cases the nodules were benign. This has implications for accurate staging. When such nodules are demonstrated on CT, comparison with a repeat scan at a suitable interval will increase diagnostic confidence.