Ten-year outcomes in a population-based cohort of node-negative, lymphatic, and vascular invasion-negative early breast cancers without adjuvant systemic therapies

Purpose To discuss the absolute benefits from adjuvant systemic therapy knowledge of long-term outcomes and baseline risks of relapse and disease-specific survival are required. We assessed the 10-year outcomes in a population-based cohort of node-negative (N-) lymphovascular negative (LV-) early breast cancers diagnosed from 1989 to 1991 who did not receive adjuvant systemic therapy. Methods One thousand one hundred eighty-seven cases of pT(1-2)N(0), LV- breast cancers with a median follow-up of 10.4 years were reviewed. Kaplan-Meier survival curves for relapse free survival (RFS), breast cancer-specific survival (BCSS) and overall survival (OS) were compared with log-rank tests with cohorts stratified for tumor size and grade. Results The median age of this series was 62 years. Four hundred thirty tumors were : 1 cm in diameter (cohort 1), 507 were 1.1-2 cm (cohort 2), and 250 were 2.1 to 5 cm in diameter (cohort 3). The 10-year outcomes for cohorts 1, 2, and 3, respectively, were significantly different: RFS, 82%, 75%, and 66%; BCSS, 92%, 90%, and 77%; and OS, 79%, 78%, and 66%. Tumor grade significantly altered outcome within size cohorts, particularly in pT(1)N(0) breast cancers. Conclusion This study provides detailed information on the continued relapse and breast cancer death rate to 10 years of follow-up. Specifically, without adjuvant systemic therapy, patients with LV-, N - breast cancer had a greater than or equal to 25% 10-year risk of relapse and a corresponding 10-year breast cancer death rate of greater than or equal to 10% if they had either a grade 3 tumor : 1 cm, a grade 2 to 3 tumor from 1.1 to 2 cm, or any grade tumor greater than 2 cm.