Potential Impact of Sentinel Lymph Node Biopsy Omission on Adjuvant Treatment Decisions in Low-Risk Breast Cancer: A Regional Multicenter 775 Patient Review of Current Practice in the United Kingdom.

BACKGROUND

Randomized controlled trials support the omission of sentinel lymph node biopsy (SLNB) in low-risk breast cancer. This study investigates the rate of nodal involvement and associated clinical factors and if the result of SLNB influences adjuvant treatment decisions.

PATIENTS AND

METHODS

All patients diagnosed with ER+ HER2- cT1N0 breast cancer ≥ 50 years were treated at three Glasgow breast cancer centers between 2022 and 2024. All patients underwent axillary ultrasound and underwent primary breast conserving surgery. Data were obtained from a prospective database of all breast cancer patients treated. Statistical analysis was performed using SPSS v.29.02.0. A chi-squared test was performed to compare categorical variables.

RESULTS

Overall, 755/775 (97.4%) patients underwent axillary surgery and 82/755 (10.9%) were node positive. Clinical and invasive pathological tumor size was significantly associated with nodal involvement [cT1a 0/19 (0.0%), cT1b 10/191 (5.2%), cT1c 70/545 (12.8%), P = 0.019; pT1a 0/41 (0.0%), pT1b 10/205 (4.9%), pT1c 52/241 (12.3%), pT2 19/82 (23.2%), P < 0.001]. Nodal involvement was significantly associated with the use of partial breast radiotherapy [node negative 262/625 (41.9%) versus node positive 0/81 (0.0%), P < 0.001]. Node-positive patients were significantly more likely to receive aromatase inhibitor therapy versus tamoxifen [75/81 (92.6%) versus 5/81 (6.2%), P < 0.001].

CONCLUSIONS

The rate of nodal involvement is low, supporting the omission of SLNB. The result of SLNB influences adjuvant treatment decisions in this low-risk cohort. Although there is enthusiasm to omit SLNB, consideration must be given to this, and omission should be performed in the context of multi-disciplinary discussions.