Survival analysis of early-stage breast cancer patients undergoing axillary lymph node dissection and sentinel lymph node dissection.

BACKGROUND: The American College of Surgeons Oncology Group (ACOSOG) Z0011 trial demonstrated equivalent survival in early-stage breast cancer (BC) patients receiving either axillary lymph node dissection (ALND) or sentinel lymph node dissection (SLND) alone. However, institutional studies have called into question the generalization of these findings outside of a clinical trial.

METHODS: Early-stage BC patients diagnosed in 2013, that received lumpectomy with whole-breast irradiation, and underwent either ALND or SLND alone, in National Cancer Database were included. Weighted Kaplan-Meier curves were used to estimate 45-month survival, accounting for demographics, comorbidities, insurance type, cancer and neighborhood characteristics.

RESULTS: 62,184 patients were included, of which 21,892 (35%) underwent ALND. Patients undergoing ALND, compared to SLND, appeared to have slightly lower survival (91.4% vs 95.1%); moreover, even after weighting, a small difference persisted (92.7% vs 94.7%, RR 0.98, 95% CI 0.97, 0.99).

CONCLUSIONS: SLND is a safe and effective alternative to ALND in BC patients with limited nodal involvement. This study provides additional evidence that the findings of ACOSOG Z0011 are applicable to the larger early-stage BC population.