Meta-analysis of the diagnostic accuracy of ultrasound-guided fine-needle aspiration and core needle biopsy in diagnosing axillary lymph node metastasis

Background: Axillary lymph node status remains a significant prognostic indicator in breast cancer. Here, the diagnostic accuracy of ultrasound-guided fine-needle aspiration (US-FNA) and ultrasound-guided core needle biopsy (US-CNB) in axillary staging was compared. Methods: A comprehensive search was undertaken of all published studies comparing the diagnostic accuracy of US-CNB and US-FNA of axillary lymph nodes in breast cancer. Studies were included if raw data were available on the diagnostic performance of both US-FNA and US-CNB, and compared with final histology results. Relevant data were extracted from each study for systematic review. Meta-analysis was performed using a random-effects model. The pooled sensitivity and specificity of US-FNA and US-CNB were obtained using a bivariable model. Summary receiver operating characteristic (ROC) graphs were created to confirm diagnostic accuracy. Results: Data on a total of 1353 patients from six studies met the inclusion criteria and were included in the final analysis. US-CNB was superior to US-FNA in diagnosing axillary nodal metastases: sensitivity 88 (95 per cent c.i. 84 to 91) versus 74 (70 to 78) per cent respectively. Both US-CNB and US-FNA had a high specificity of 100 per cent. Reported complication rates were significantly higher for US-CNB compared with US-FNA (7·1 versus 1·3 per cent; P < 0·001). Conversely, the requirement for repeat diagnostic procedures was significantly greater for US-FNA (4·0 versus 0·5 per cent; P < 0·001). Conclusion: US-CNB is a superior diagnostic technique to US-FNA for axillary staging in breast cancer.