US-CNB Biopsy Improves Breast Cancer Staging

A new study shows that ultrasound-guided core-needle biopsy (US-CNB) bests ultrasound-guided fine-needle aspiration (US-FNA) when diagnosing axillary lymph node metastasis.

Researchers at the National University of Ireland Galway (NUI Galway; Ireland) and Cork University Hospital (CUH; Ireland) conducted a meta-analysis of all published studies comparing the diagnostic accuracy of axillary lymph node ultrasound-guided biopsy. 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. In all, from a total of 142 studies, six remained after review, with all six showing some evidence of bias, including ack of initial randomization.

The results, based on the data of 1,353 patients from the six studies that met inclusion criteria and were included in the final analysis, revealed that US‐CNB was superior to US‐FNA in diagnosing axillary nodal metastases, with a sensitivity of 88% versus 74%, respectively; both US‐CNB and US‐FNA demonstrated a specificity of 100%. Reported complication rates were significantly higher for US‐CNB (7.1%) compared with US‐FNA (1.3%). Conversely, the requirement for repeat diagnostic procedures was significantly greater for US‐FNA (4%), compared to 0.5% for US‐CNB. The study was published in the September 2018 issue of BJS.

“There is continued need to access the axillary status of patients with breast cancer because it is crucial for further therapeutic decisions. Although both procedures performed reasonably well, US-CNB was the preferred choice, mainly because of the reduced number of patients who needed a repeat biopsy,” concluded lead author Ishwarya Balasubramanian, MCh, of GUH. “It is hard to evaluate the significance of postoperative complications, because in three of the six included studies US-FNA was followed by US-CNB, making it difficult to determine which of the two procedures was responsible for the postoperative complication.”

FNA is a diagnostic procedure used to investigate lumps or masses, which involves inserting a thin, hollow needle into the mass for sampling of cells that, after being stained, will be examined under a microscope. CNB uses a larger diameter needle to remove a section of tissue from a lesion or mass. The advantages of CNB over FNA include obtaining a more definitive histologic diagnosis and more adequate sampling for immunohistochemistry evaluation.

Related Links:
National University of Ireland Galway
Cork University Hospital