T1a Breast Carcinoma And The Role Of Axillary Dissection

Hypothesis: Axillary dissection (AD) does not affect recurrence or survival in T1a breast cancer.Design: Cohort study comparing patients who underwent AD and those who did not.Setting: Provincial cancer agency.Patients: Six hundred ninety-one women with pathologically diagnosed T1a tumors.Main Outcome Measures: Rates of axillary metastases stratified according to grade and lymphovascular and/or neural invasion, rates of relapse, and disease-specific survival.Results: Grade 1, 2, and 3 tumors without lymphovascular and/or neural invasion had axillary nodal involvement rates of 0.7%, 7%, and 7.8% of patients, respectively; with lymphovascular and/or neural invasion, axillary nodes were involved in 9.1%, 39.3%, and 44.4%, respectively. No statistically significant differences were found between the cohorts in relapse rates (P = .70) or survival (P = .84).Conclusion: Higher tumor grade and lymphovascular and/or neural invasion increased the rate of nodal metastases in T1a tumors, but AD did not improve relapse rates or breast cancer-specific survival.