BREAST-CONSERVATION TREATMENT OF EARLY-STAGE BREAST-CANCER - PATTERNSOF FAILURE

Purpose: This study retrospectively assesses the patterns of failure i n conservatively treated early stage breast cancer patients by correla ting various clinical, pathologic, and treatment-related factors with local, axillary, and distant relapse. Methods and Materials: Between 1 973 and 1990, 796 patients (817 breasts) received breast conservation surgery followed by radiotherapy. Local recurrences were counted as ev ents even if they occurred simultaneously or after the appearance of a xillary or distant metastases. Results: The 10-year actuarial relative disease-free survival (DFS) rate for T1N0, T2N0, and T1-2N1 was 82%, 71%, and 54%, respectively. Stage N0 patients had a significant DFS ad vantage over N1 patients (p = 0.02). The 15-year actuarial local recur rence-free rate for T1 and n tumors was 82% and 87%, respectively (p = nonsignificant). Univariate analysis identified three significant ris k factors for local relapse: (a) 48 breasts with tumors showing an ext ensive intraductal component had a crude local recurrence rate of 23% compared to 8% for 769 breasts without intraductal component (p = 0.00 16); (b) the actuarial 10-year local recurrence-free rate for patients under age 40 years was 64% compared to 88% for patients over 40 years (p < 0.0001); (c) the 10-year actuarial local recurrence-free rate fo r 416 postmenopausal women without adjuvant tamoxifen was 83% compared to 97% for 107 postmenopausal women with tamoxifen (p = 0.0479). Salv age therapy for operable local recurrent patients resulted in a 8-year actuarial DFS rate of 47%, significantly lower than that obtained wit h primary treatment. The incidence of axillary relapse as the first si gn of recurrence was 2%, and could be correlated with the lack of axil lary dissection (p < 0.0000005) and primary tumor size (p = 0.03), Rad iotherapy to the axilla did not influence axillary relapse. Actuarial 5-year DFS rate after treatment of isolated axillary recurrence was 27 %. Axillary failure was a marker for distant failure. Contralateral br east cancer occurred in 8% of patients and did not have a detrimental effect on survival. Adjuvant tamoxifen decreased the 9-year actuarial incidence of contralateral breast cancer from 10% to 4% (p = 0.053). C onclusions: Tumors with extensive intraductal component, age under 40 years, and the omission of adjuvant tamoxifen in postmenopausal women increased local recurrence rate. Stage T2 and the lack of axillary dis section increased axillary recurrence rate. Stage N+ and local or axil lary relapse increased distant failure rate. Axillary irradiation did not influence locoregional control nor survival. Improved therapy is n eeded for relapsing patients.