Sentinel-Lymph-Node-Based Management or Routine Axillary Clearance? Five-Year Outcomes of the RACS Sentinel Node Biopsy Versus Axillary Clearance (SNAC) 1 Trial: Assessment and Incidence of True Lymphedema.

PURPOSE: To determine whether the benefits of sentinel-node-based management (SNBM) over routine axillary clearance (RAC) persisted to 5 years.

METHODS: A total of 1088 women with breast cancer less than 3 cm in diameter and clinically negative axillary nodes were randomized to SNBM with axillary clearance if the sentinel node was positive or RAC preceded by sentinel-node biopsy. The outcomes were: (1) objectively measured change in the volume of the operated and contralateral nonoperated arms; (2) the proportion with an increase in arm volume <15%; and (3) subjectively assessed arm morbidity for the domains swelling, symptoms, dysfunction, and disability. Assessments were performed at 1 and 6 months after surgery and then annually.

RESULTS: Limb volume increased progressively in the operated and nonoperated arms for 2 years and persisted unchanged to year 5, accompanied by weight gain. Correction by change in the nonoperated arm showed a mean volume increase of 70 mL in the RAC group and 26 mL in the SNBM group (P < 0.001) at 5 years. Only 28 patients (3.3%) had a corrected increase >15% from baseline (RAC 5.0% vs. SNBM 1.7%). Significant predictors were surgery type (RAC vs. SNBM), obesity, diabetes, palpable tumor, and weight gain exceeding 10% of baseline value.

CONCLUSIONS: Subjective assessments revealed persisting patient concerns about swelling and symptoms but not overall disability at 5 years. Subjective scores were only moderately correlated with volume increase. SNAC1 has demonstrated that objective morbidity and subjective morbidity persist for 5 years after surgery and that SNBM significantly lowers the risk of both.