Reappraisal of the role of axillary lymph node dissection in the conservative treatment of breast cancer.

Purpose: The purpose of this study was (1) to review systemic therapy practice patterns to assess how information regarding nodal status currently influences systemic therapy decisions, and (2) to review long-term outcome of patients who do not undergo axillary dissection compared with patients who do.

Methods And Materials: For the current practice patterns portion of the study, the records of 292 patients who presented in the past 3 years with invasive breast cancer and underwent conservative surgery were reviewed to determine systemic therapy administered with respect to patient age, primary tumor size, clinical nodal status, and presenting symptoms. For the long-term outcome portion of the study, the records of 955 patients with invasive breast cancer who underwent conservative surgery and radiation therapy before December 1989 were reviewed. Patient characteristics and outcome of those patients who underwent axillary dissection (n = 565, 59%) were compared with a cohort of patients treated during the same era who did not undergo axillary dissection (n = 390, 41%).

Results: For the current practice-patterns cohort, information regarding nodal status appeared to influence adjuvant systemic therapy for those patients less than 50 years of age and for those patients with palpable masses who were older than 50. Patients older than 50 with nonpalpable mammographically detected tumors have a low probability of nodal involvement and information regarding nodal status rarely changed therapy in this group of patients. In the long-term outcome study, there were no significant differences in the rates of distant metastasis, disease-free survival, or overall survival between those patients who underwent lymph node dissection and those who did not.

Conclusion: For selected patients, axillary lymph node dissection appears to have little influence on subsequent management and long-term outcome. These data suggest that it is time to reassess the role of axillary lymph node dissection in patients who undergo conservative surgery and radiation therapy.