Preoperative axillary imaging with percutaneous lymph node biopsy is valuable in the contemporary management of patients with breast cancer

Background. ACOSOG Z11 and other studies showing little benefit to axillary dissection (ALND) for early-stage breast cancers with limited nodal disease have led to questioning the value of preoperative axillary imaging +/- ultrasound-guided needle biopsy (USNB). Data are lacking on the value of this approach in identifying cases that fall outside Z11 guidelines. Methods. We studied 988 consecutive patients with invasive breast cancers who underwent operation including axillary surgery in 2010-2011. Results. Preoperative axillary ultrasonography (A US) was performed in 92% and breast/axillary magnetic resonance imaging (MRI) in 51%; 82 (33.5%) of 245 patients with suspicious lymph nodes (LN) were USNB-positive. Regarding nodal status, AUS, MRI, and USNB had negative and positive predictive values of 78%, 76%, 70% and 54%, 58%, 100%, respectively. AUS/MRI visualization of one versus multiple abnormal LNs visualized predicted > 2LN+ on final pathology (13.5%/15.1% % vs 30.8%/32.6%, P < .009). Among USNB-LN+ T1/T2 patients, 51.6% had 1-2 LN+ while 60% with multiple and 31% with one AUS-abnormal LN(s) had > 2LN+, P = .001. Conclusion. In our contemporary series, preoperative AUS USNB streamlined surgical care for 29% of node-positive patients. Two-thirds of T1/T2 USNB-LN+ patients with multiple AUS-suspicious LNs had > 2LN+, suggesting they should undergo ALND without SLNB. AUS +/- USNB helps identify node-positive breast cancer patients who fall outside Z11 guidelines.