Microbubble detection and ultrasound-guided vacuum-assisted biopsy of axillary lymph nodes in patients with breast cancer

Abstract

To assess the feasibility of undertaking microbubble-guided vacuum-assisted biopsy (VAB) of the sentinel lymph node (SLN) and determine its sensitivity in detecting metastases. Patient experience and the impact of VAB on subsequent axillary surgery were also evaluated. Patients with a normal axillary ultrasound or benign core biopsy planned for surgical SLN biopsy were recruited. Part 1 of the study was used to establish the technique of ultrasound microbubble contrast to detect the SLN. In Part 2 microbubble detection of the SLN was followed by 13 G VAB. All patients subsequently had surgical histological correlation. One hundred and thirty-nine patients were recruited: 36 to Part 1 and 103 to Part 2. Of the 100 patients in Part 2 included for analysis, 82 (82%) underwent successful biopsy. Sensitivity for detecting metastases was 58.8% (95% confidence interval: 32.9%, 81.6%). The procedure was generally well tolerated; however, VAB interfered adversely with subsequent surgical SLN biopsy with surgeons reporting moderate or severe interference in 48% of patients and an additional 8.3% with complete failure of SLNB. It is possible to perform VAB of microbubble-detected SLNs. Although the sensitivity for detecting metastases was reasonable, the adverse effect on subsequent surgery was significant.