Immediate Surgery Lowers Local Recurrence in Older Breast Cancer Population

“In the absence of radiotherapy, we see that immediate compared with deferred surgery greatly reduces local recurrence. This benefit in local recurrence translates into a later difference in distant recurrence and breast cancer [mortality], but it’s only apparent with long follow-up," according to study author Robert Hills.

Immediate surgery showed significant reductions in local recurrence compared with delaying surgery until after disease progression among elderly patients with breast cancer, according to findings from a meta-analysis presented at the 2024 San Antonio Breast Cancer Symposium (SABCS).

Among 656 patients with node-negative disease, the rate of isolated local recurrence at 5 years was 45.4% for those who received tamoxifen (Soltamox) alone vs 14.4% for patients who received tamoxifen in combination with surgery (rate ratio [RR], 0.25; 95% CI, 0.19-0.34; P <.00001). For 262 patients with node-positive disease, the 5-year rates of isolated local recurrence were 48.1% vs 6.8% in each respective group (RR, 0.18; 95% CI, 0.11-0.29; P <.00001). Data showed that characteristics such as tumor size or trial did not impact local recurrence outcomes achieved with immediate surgery.

In the tamoxifen alone and tamoxifen/surgery groups, respectively, the rates of distant recurrence were 24.4% vs 20.7% at 5 years, 39.5% vs 30.9% at 10 years, and 51.3% vs 37.0% at 15 years (RR, 0.72; 0.57-0.90; P = .003). In each respective group, the rates of breast cancer mortality were 16.0% vs 11.9% at 5 years, 33.6% vs 25.9% at 10 years, and 48.9% vs 34.2% at 15 years (RR, 0.68; 95% CI, 0.54-0.86; P = .002). Findings showed that immediate surgery conferred little effect on distant recurrence or breast cancer mortality outcomes compared with tamoxifen alone within 1 year of treatment.

The rates of all-cause mortality with tamoxifen alone and tamoxifen/surgery, respectively, were 31.8% vs 26.1% at 5 years, 65.8% vs 61.8% at 10 years, and 88.7% vs 82.2% at 15 years (RR, 0.83; 95% CI, 0.72-0.97; P = .016). Overall, investigators noted that were was no evidence of immediate surgery producing any effect on non–breast cancer mortality.

“In the absence of radiotherapy, we see that immediate compared with deferred surgery greatly reduces local recurrence. This benefit in local recurrence translates into a later difference in distant recurrence and breast cancer [mortality], but it’s only apparent with long follow-up," study author Robert Hills stated in the presentation. “The results will be greatly [supplemented] by the updated analysis of the NSABP B-06 trial of mastectomy vs lumpectomy.”

Hills is a professor of Medical Statistics in the Nuffield Department of Population Health at the University of Oxford and head of the Secretariat for the Early Breast Cancer Trialists’ Collaborative Group.

According to Hills, rates of surgery tend to diminish as patients with breast cancer become older, especially among individuals above the age of 80 years. With this background in mind, investigators aimed to assess whether immediate surgery plus tamoxifen improved outcomes among elderly patients with breast cancer compared with delaying surgery until patients experience progressive disease.

Investigators conducted a patient-level meta-analysis of data on 1082 individuals with breast cancer who were 70 years and older across 3 clinical trials evaluating immediate surgery vs deferral in the absence of radiotherapy. Patients included in the analysis remained on the study for a median of 5 years.

The main outcomes of the analysis were local recurrence, distant recurrence, and mortality.

“These results are relevant today, methodologically, because what they tell us is that even with large differences in local therapy—surgery vs no surgery—the benefits only occur with longer follow-up,” Hills concluded. “Trials that compare local therapy or screening need to be followed up for long enough to see whether any benefits emerge.”

Reference

Hills RK, Bradley R, Braybrooke J, et al. Immediate breast surgery versus deferral of surgery in women aged 70+ years with operable breast cancer: patient-level meta-analysis of the three randomised trials among 1,082 women. Presented at the 2024 San Antonio Breast Cancer Symposium; December 10-13, 2024; San Antonio, TX. LB1-01.