LAUSR

Introduction: Sentinel lymph node biopsy (SLNB) is the reference standard for axillary staging in all patients with invasive breast cancer. Surgical practices are being reviewed for a more conservative approach to the axilla. Patients and Methods: In this audit, we studied the incidence of axillary disease in patients with ultrasound negative axilla. The selection criteria are similar to an ongoing national study: female patients, age > 50 years, primary breast lesion < 1.5 cm in size, and estrogen receptor–positive and HER‐2 (human epidermal growth factor receptor 2)‐negative disease. We studied the data of all breast cancer patients, January 2013 to December 2015, in a population of 350,000 with annual incidence of about 400 cancers. Results: In our patient subset, we studied a total of 261 patients. The average false‐negative (FN) rate with axillary ultrasound (AUS) per year was noted to be 10.7% (P = .0052). This is comparable to SLNB, which has a FN rate of approximately 10%. The sensitivity of AUS to exclude axillary disease was 89.3% (95% confidence interval, 84.9–92.3). Conclusion: Because the FN rate of AUS and SLNB are comparable, the former can possibly replace the latter, at least in a subset of early breast cancer patients. This finding has wide implications. Micro‐Abstract: Sentinel lymph node biopsy (SLNB) has long been the mode of staging of the axilla in invasive breast cancer. We studied the incidence of axillary disease in patients with ultrasound negative axilla in a selected group of patients. We noted that the false negative rate of axillary ultrasound and SLNB was comparable in a subset of early breast cancer patients.