Background: The purpose of this study is to determine the impact of adjuvant systemic chemotherapy and adjuvant hormonal therapy on local relapse in the conservatively treated breast.
Materials and methods: Before December 1989, 548 patients underwent lumpectomy with axillary dissection followed by radiation therapy to the intact breast. Adjuvant systemic therapy was administered as clinically indicated. The majority of patients with pathologically involved lymph nodes received adjuvant systemic therapy, whereas those with pathologically negative lymph nodes received no adjuvant systemic therapy. The majority of patients received a course of radiation therapy either concomitant with or before systemic therapy. In only nine cases was radiation therapy delayed more than 16 weeks after surgery.
Results: As of June 1992, the 548 patients had a median follow-up of 6.4 years. In univariate and multivariate Cox regression analysis, patient age and adjuvant systemic chemotherapy were statistically significant independent prognostic factors relating to breast relapse. Those patients who received adjuvant systemic chemotherapy had a lower breast relapse than those who did not. Among patients who received tamoxifen, there was a statistically insignificant trend toward a lower relapse rate compared with those who did not receive tamoxifen.
Conclusions: It appears from this retrospective analysis that patients who received adjuvant systemic therapy, either concomitantly or after their course of radiation therapy, had a lower relapse rate in the conservatively treated breast than those patients who received no adjuvant systemic therapy.