Clinical value of contrast-enhanced ultrasound in transthoracic biopsy of malignant anterior mediastinal masses

Abstract

Background: Given low incidence and high heterogeneity, the treatment strategies of anterior mediastinal masses (AMMs) are diverse based on pathology. The purpose of the study is to evaluate the usefulness of contrast-enhanced ultrasound (CEUS) in transthoracic biopsy of malignant AMMs when compared with that of ultrasound (US) alone and to screen lesions that are more suitable for CEUS evaluation and guidance. Methods: We reviewed all the US- and CEUS-guided transthoracic core needle biopsy (CNB) of AMMs performed in National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College between July 2013 and April 2019. A total of 68 patients (mean age 36 years; male-female ration 1.6:1) who were suspected with malignant AMMs were enrolled in the study. Among them, 20 patients received pre-biopsy CEUS examination (CEUS group); 48 patients underwent conventional US examination and guidance (US group). Demographic, radiologic, pathologic, medical records, and biopsy procedure details were retrospectively reviewed and compared between the two groups. Results: The display of internal necrosis areas was significantly improved when compared with that of the conventional US (70%, 30%; P=0.008). Specifically, CEUS improved the diagnostic accuracy of US-guided transthoracic biopsy (95.0%, 79.2%; P=0.210) and especially for AMMs exceeding 10 cm (100%, 68.2%; P=0.040) and carcinoma (100%, 0%; P=0.048). The number of punctures in US group and CEUS group was 2.6 and 4.4 times, respectively (P<0.001). In case of similar number of punctures (1 to 3 times), CEUS improved diagnostic accuracy when compared to that of the conventional US (100%, 75%; P=0.486). The technical success rate was 100% (68/68). In both groups, patients did not exhibit symptomatic complications such as bleeding, pneumothorax, or hemoptysis after the biopsy. Conclusions: The application of CEUS in transthoracic biopsy of malignant AMMs improved diagnostic accuracy when compared with conventional US and especially played more important role in lesions exceeding 10 cm and presumptive clinical carcinoma.