Breast Oncology Research Updates

This single-center retrospective cohort of 246 patients with de novo extra‑nodal metastatic breast cancer who underwent breast surgery compared axillary lymph node dissection (ALND) versus sentinel lymph node biopsy (SLNB) or no axillary surgery. After a median follow-up of ~60 months and using IPTW-adjusted analyses, ALND was not associated with improved progression-free or overall survival (HRs not statistically significant) and patterns of disease progression, including nodal progression, were similar between groups.

In tumor-bearing mouse models (established melanoma and additional colorectal and triple-negative breast cancer models), a single dose of cyclophosphamide given one day before combined anti–PD-1 and anti–CTLA-4 immune checkpoint blockade delayed tumor progression and prolonged survival compared with ICB alone. The enhanced antitumor effect—also observed when other lymphodepleting treatments such as gemcitabine or radiation were used—was driven primarily by clonal expansion of activated/effector CD8+ tumor-infiltrating lymphocytes.

Using a simulation model of 5-year survivors of pediatric Hodgkin lymphoma based on cohort and national data, projected survival and cumulative incidence of breast cancer and heart failure were compared across treatment exposures (extended-field RT, chest RT ≥35 Gy, chest RT <35 Gy, and chemotherapy only) versus the general population. By age 65, projected overall survival was lowest after extended-field RT and highest after chemotherapy only, and female survivors treated with RT had markedly elevated cumulative breast cancer incidence while all survivor groups had substantially higher heart failure risks and earlier onset of these events compared with the general population.