The effect of the amount of peritumoral adipose tissue in the detection of additional tumors with digital breast tomosynthesis and ultrasound.

Background Digital breast tomosynthesis (DBT) and ultrasound (US) can detect additional cancers after negative mammography. However, not all cancers are visible by both techniques. Purpose To study the role of the amount of peritumoral fat in the detection of additional cancers with DBT or US. Material and Methods One reader retrospectively reviewed 142 breast cancers in 109 women who underwent mammography, DBT, US, and magnetic resonance imaging (MRI). Two readers in consensus evaluated the additional cancers detected by US, DBT, or MRI, and classified them into four groups according to the amount of peritumoral adipose tissue: group I, >75% of peritumoral fat; group II, 50-74%; group III, 25-49%, and group IV, 0-24%. The detection of additional cancers by US and DBT with respect to the other imaging techniques was evaluated. Results Seventy-eight cancers were detected by mammography and the remaining 64 cancers were detected by DBT, US, or MRI. US and DBT detected 46 (71.8%) and 25 (39.06%) additional tumors, respectively. Statistical significance was only found in group IV ( P < 0.01). Conclusion US detected more tumors than DBT in lesions surrounded by a small amount of fat. No significant differences were found between US and DBT in the detection of additional cancers in the other groups.

Diagnostic performance of endorectal ultrasound combined with shear wave elastography for rectal tumors staging.

OBJECTIVE: This study aims to analyze the performance of endorectal ultrasound (ERUS) combined with shear wave elastography (SWE) for rectal tumor staging. METHODS: Forty patients with rectal tumors who had surgery were enrolled. They underwent ERUS and SWE examinations before surgery. Pathological results were used as the gold standard for tumor staging. The stiffness values of the rectal tumor, peritumoral fat, distal normal intestinal wall, and distal perirectal fat were analyzed. The diagnostic accuracy of ERUS stage, tumor SWE stage, ERUS combined with tumor SWE stage, and ERUS combined with peritumoral fat SWE stage were compared and evaluated by receiver operating characteristic (ROC) curve to select the best staging index. RESULTS: From T1 to T3 stage, the maximum elasticity (Emax) of the rectal tumor increased gradually (p < 0.05). The cut-off values of adenoma/T1 and T2, T2 and T3 tumors were 36.75 and 85.15kPa, respectively. The diagnostic coincidence rate of tumor SWE stage was higher than that of ERUS stage. Overall diagnostic accuracy of ERUS combined with peritumoral fat SWE Emax restaging was significantly higher than that of ERUS. CONCLUSIONS: ERUS combined with peritumoral fat SWE Emax for tumor restaging can effectively distinguish between stage T2 and T3 rectal tumors, which provides an effective imaging basis for clinical decisions.

Peritumoral Fat Content Correlates with Histological Prognostic Factors in Breast Carcinoma: A Study Using Iterative Decomposition of Water and Fat with Echo Asymmetry and Least-Squares Estimation (IDEAL).

PURPOSE: To correlate peritumoral fat content using iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) with histologic prognostic factors in breast carcinoma. MATERIALS AND METHODS: This study consisted of 100 patients who were diagnosed with invasive carcinoma of breast and underwent breast MRI including IDEAL before surgery. The scan time of IDEAL fat fraction (FF) map imaging was 33 s. Four regions of interests (ROIs), which are a distance of 5 mm from the tumor edge, and one ROI in the mammary fat of the healthy side were set on the FF map. Then average peritumoral FF values (FFt), average FF values in the healthy side (FFh), and peritumoral fat ratio (pTFR: defined as FFt/FFh) were calculated. Histologically, the presence of lymph node metastasis and the MIB-1 index were evaluated. RESULTS: FFt and pTFR for breast carcinoma with lymph node metastasis (79.27 ± 10.36 and 0.897 ± 0.078) were significantly lower than those without (86.23 ± 4.53 and 0.945 ± 0.032) (P < 0.001 and P = 0.005). Spearman rank correlation suggested that the FFt correlated with the MIB-1 index (r = -340, P = 0.001). CONCLUSION: Quantification of peritumoral fat using IDEAL-iron quantification is associated with the histologic prognostic factors, and may be a practical tool for therapeutic strategy of breast carcinoma.

Contrast-enhanced ultrasonography evaluation of hepatocellular carcinoma with peritumoral fat-spared area: a case report.

Peritumoral fat-spared area (PTFSA), a focal spared area surrounding hepatic tumors, is a specific finding of liver tumors in fatty livers. PTFSA mimics a liver tumor, making it difficult to recognize the tumor boundary. We report a case of a 56-year-old man with fatty liver who was diagnosed with a liver tumor. Ultrasonography (US) revealed a nearly homogeneous hyperechoic liver tumor measuring 40 mm in the left lobe. A thick hypoechoic area was observed around the tumor that spread more widely than an ordinary halo. Histological examination revealed that the hypoechoic area comprised a thin fibrous capsule and normal liver parenchyma without fat, which is PTFSA. Contrast-enhanced US (CEUS) indicated corona enhancement only at the inner part of the PTFSA. The inner part showed the same pattern as that of an ordinary halo and was a part of hepatocellular carcinoma, whereas the outer part showed the same pattern as that of the other liver parenchyma. CEUS was an effective modality for distinguishing the difference. Thus, CEUS was useful in defining the tumor boundary. Before initiating treatment, tumors should be evaluated using various modalities to detect their accurate boundary. CEUS may be a useful modality for detecting the boundary and making a diagnosis.