A Multicenter Randomized Controlled Study of Contrast-enhanced US versus US-guided Biopsy of Focal Liver Lesions.

Background Retrospective or single-center prospective studies with relatively small samples have shown that contrast-enhanced US (CEUS) can improve the diagnostic accuracy of percutaneous biopsy, but larger prospective studies are lacking. Purpose To assess the diagnostic performance of CEUS-guided biopsy (CEUS-GB) of focal liver lesions (FLLs) compared with US-guided biopsy (US-GB) in a prospective multicenter study. Materials and Methods In this randomized controlled study conducted in nine hospitals in China between March 2016 and August 2019, adult participants with FLLs detected with US, CT, or MRI and planned for percutaneous biopsy were randomly assigned to undergo either US-GB or CEUS-GB. Lesions diagnosed as malignant at histopathologic analysis were considered true-positive findings. Benign or indeterminate lesions required further confirmation with either repeat biopsy or clinical follow-up at 6 months or later. The primary endpoint was the diagnostic accuracy rate, and comparison between groups was made using the χ2 test. Results In this study, 2056 participants (1297 men, 759 women; mean age, 58 years ± 11 [SD]) were analyzed: 1030 underwent biopsy with US guidance and 1026 underwent biopsy with CEUS guidance. The overall diagnostic accuracy rate of CEUS-GB was 96% (983 of 1026) versus 93% (953 of 1030) for US-GB (P = .002), CEUS-GB enabled correct identification in 96% of participants (983 of 1026) compared with 92% (953 of 1030) with US-GB (P = .002). The negative predictive value (NPV) for both biopsy methods was moderate but significantly higher for CEUS-GB than for US-GB (74% vs 57%, P = .001). The difference was remarkable for lesions smaller than 2.0 cm, with CEUS-GB showing higher diagnostic accuracy (96% vs 88%, P = .004) and sensitivity (95% vs 87%, P = .007) than US-GB. Among lesions smaller than 2.0 cm, the accuracy of CEUS-GB and US-GB for detection of hepatocellular carcinoma was 93% and 80%, respectively (P = .008), while it was comparable for liver metastases (98% vs 95%, P = .63). Conclusion Contrast-enhanced US-guided biopsy of focal liver lesions is an effective and safe procedure with a higher diagnostic accuracy than US-guided biopsy, especially for lesions smaller than 2.0 cm and for hepatocellular carcinoma diagnosis. Clinical trial registration no. NCT02413437 © RSNA, 2022 Online supplemental material is available for this article.

Cross-Fostering of Male Mice Subtly Affects Female Olfactory Preferences.

The maternal environment has been shown to influence female olfactory preferences through early chemosensory experience. However, little is known about the influence of the maternal environment on chemosignals. In this study, we used two inbred mouse strains, C57BL/6 (C57) and BALB/c (BALB), and explored whether adoption could alter male chemosignals and thus influence female olfactory preferences. In Experiment 1, C57 pups were placed with BALB dams. Adult BALB females then served as the subjects in binary choice tests between paired male urine odours (BALB vs. C57, BALB vs. adopted C57 and C57 vs. adopted C57). In Experiment 2, BALB pups were placed with C57 dams, and C57 females served as the subjects in binary choice tests between paired male urine odours (C57 vs. BALB, C57 vs. adopted BALB, and BALB vs. adopted BALB). In both experiments, we found that females preferred the urine of males from different genetic backgrounds, suggesting that female olfactory preferences may be driven by genetic compatibility. Cross-fostering had subtle effects on female olfactory preferences. Although the females showed no preference between the urine odours of adopted and non-adopted males of the other strain, the BALB females preferred the urine odour of BALB males to that of adopted C57 males, whereas the C57 females showed no preference between the urine odour of C57 and adopted BALB males. Using gas chromatography-mass spectrometry (GC-MS) and stepwise discriminant analysis, we found that the ratios of volatile chemicals from urine and preputial gland secretions were altered in the fostered male mice; these changes may have resulted in the behavioural changes observed in the females. Overall, the results suggest that female mice prefer urine odours from males with different genetic backgrounds; this preference may be driven by genetic compatibility. The early maternal environment influences the chemosignals of males and thus may influence the olfactory preferences of females. Our study provides additional evidence in support of genotype-dependent maternal influences on phenotypic variability in adulthood.