Axillary Ultrasound Fine Needle Aspiration Biopsy: Is There a Role in the Post Z-0011 Era?
Axillary ultrasound with fine needle aspiration (AXUSFNA) in early-stage breast cancer has required reappraisal. ACOSOG Z-0011 and after mapping of the axilla: radiotherapy or surgery have shown that women with limited nodal disease at sentinel lymph node biopsy got no survival advantage with completion axillary node dissection. We hypothesize that AXUSFNA may be sufficiently accurate for staging for some patients and sentinel lymph node biopsy need not be performed. We define the false negative rate (FNR) of AXUSFNA in different subsets of patients.Materials and Methods:
This retrospective cohort study included node positive patients who also underwent AXUSFNA between 1/2006 and 12/2010 followed by axillary surgery. The FNR was calculated for the entire group and for subgroups determined by tumor, nodal, and ultrasound findings.Results:
Out of ∼700 AXUSFNA patients, 128 node positive patients were included in the study. The overall AXUSFNA FNR was 35.9% (95% confidence interval, 28.1%-44.6%). There was a significantly higher FNR with smaller tumors and presence of ductal carcinoma in situ on multivariate analysis. On ultrasound, benign-appearing nodes had a higher FNR than indeterminate nodes (78.9% vs. 60.9%, P=0.2) and significantly higher than suspicious nodes (78.9% vs. 2.9%, P<0.0001).Conclusions:
In our cohort, the FNR for AXUSFNA was comparable with the rate of residual disease in the control arms of Z-0011 (27.4%) and after mapping of the axilla: radiotherapy or surgery (33%). However, our analysis suggests that we may be able to identify more appropriate patients for AXUSFNA and halve the FNR. As primary tumor characteristics and genomics drive systemic therapeutic recommendations, there may be an ongoing role for AXUSFNA in axillary staging.