Can high frequency ultrasound predict metastatic lymph nodes in patients with invasive breast cancer?

Abstract 

Purpose

Use high frequency ultrasound to predict the presence of metastatic axillary lymph nodes, with a high specificity and positive predictive value, in patients with invasive breast cancer. The clinical aim is to improve the surgical management and possible survival rate of groups of patients who would not normally have conventional axillary dissections.

Materials and methods

The ipsilateral and contralateral axillas of 42 consecutive patients with invasive breast cancer were scanned prior to treatment using a B-mode frequency of 13MHz and a Doppler frequency of 7MHz. The presence or absence of an echogenic centre for each lymph node detected was recorded, measurements were also taken to determine the L/S (long axis/short axis) ratio of the node and the widest and narrowest part of the cortex. Power Doppler was also used to determine vascularity. The contralateral axilla was used as a control for each patient.

Results

In this study of patients with invasive breast cancer, where ipsilateral lymph nodes had a cortical bulge of ≥3mm and/or at least two lymph nodes had absent echogenic centres, all had disease spread to the axillary lymph nodes (10 patients). Sensitivity and specificity were 52.6% and 100%, respectively, positive and negative predictive values were 100% and 71.9%, respectively, the P-value was 0.001 and the Kappa score was 0.55.

Conclusion

This would indicate that high frequency ultrasound could be used to accurately predict metastatic lymph nodes in a proportion of patients with invasive breast cancer, which may alter patient management.

Keywords: Sonography, Axilla, In vivo, Sentinel node, Surgery