Between 1977 and 1985, 697 women with clinical Stage I or II invasive breast cancer underwent excisional biopsy, axillary dissection, and definitive irradiation. Reexcision of the primary was performed in 330 and residual tumor was identified in 57% of these patients. Margins of resection were assessed in 50% and 257 had final margins of resection that were negative. Four hundred eighty patients had negative axillary dissections and 217 had histologically positive axillary nodes. Median follow-up was 58 months. The 10-year actuarial survival for the entire group was 83% with an NED survival of 73%. The 10-year actuarial survival was 87% for clinical Stage I and 77% for clinical Stage II patients with an NED survival of 79% and 67%, respectively. Patients with histologically negative axillary nodes had a 10-year overall survival of 86% (NED 78%) compared to 74% (NED 66%) for patients with positive nodes. Sixty-one patients developed a recurrence in the treated breast and in seven of these it was associated with simultaneous distant metastases. The cumulative probability of an isolated breast recurrence was 6% at 5 years and 16% at 10 years. The overall breast recurrence rate (+/- distant metastasis) was 8% at 5 years and 18% at 10 years. Breast recurrence was unrelated to T size, clinical stage, or histologic nodal status. The addition of adjuvant chemotherapy significantly decreased the risk of an isolated breast recurrence both at 5 and 10 years; however, there was no significant impact on the overall risk of a breast recurrence. Complications of treatment included moderate arm edema (5%), symptomatic pneumonitis (less than 1%), rib fraction (1%), pericarditis (0%), and brachial plexopathy (less than 1%). Cosmesis was judged to be good to excellent in 93% of patients in 10 years. These results have been achieved in a series of patients who for the most part have been treated by contemporary standards, that is, pathologic assessment of the axilla in all patients, reexcision in 47%, and adjuvant chemotherapy in 77% of node positive patients. Assessment of resection margins, however, was not performed in all patients (50%) and further follow-up in the group of patients with margin assessment will provide long term information on breast recurrence rate in this group of patients.