Relapse and morbidity in patients undergoing sentinel lymph node biopsy alone or with axillary dissection for breast cancer.

HYPOTHESIS Axillary relapse in node-negative patients staged with sentinel lymph node (SLN) biopsy alone is no more frequent than in patients treated with standard axillary dissection. Morbidity is less for patients who had SLN biopsy. DESIGN, SETTING, AND PATIENTS Between October 14, 1997, and August 31, 2001, 1253 consecutive women with primary invasive breast cancer were prospectively entered into an SLN biopsy database. Completion axillary dissection was performed in 164 patients after SLN biopsy as part of a training protocol. INTERVENTIONS Patients were contacted by questionnaire or telephone to determine breast cancer relapse; presence of arm lymphedema, arm pain, axillary infection, or seroma formation; and tumor recurrence or death. MAIN OUTCOME MEASURES chi2 or Fisher exact tests and Wilcoxon rank sum tests were used to analyze categorical and continuous variables. Logistic regression was used to analyze morbidity. RESULTS Of 1253 women, 894 (71%) were node negative by SLN biopsy alone (n = 730 [82%]) or SLN biopsy and completion axillary dissection (n = 164 [18%]). Questionnaires were completed by 776 patients (87%). Mean +/- SD follow-up was 2.4 +/- 0.9 years. Patients with axillary dissections reported a significantly higher occurrence of arm lymphedema (34%), arm pain (38%), seroma formation (24%), and infection (9%) vs SLN biopsy-only patients (6%, 14%, 7%, and 3%, respectively). One axillary relapse (0.1%) occurred during follow-up of 685 women who underwent SLN biopsy only. CONCLUSIONS With intermediate-term follow-up, there was 1 axillary recurrence in 685 SLN node-negative women, supporting use of SLN biopsy as an accurate method for staging breast cancer. Biopsy of the SLN was associated with significantly less morbidity than completion axillary dissection.