Factors Influencing the Occurrence of Anemia During Adjuvant and Neoadjuvant Chemotherapy in the Treatment of Breast Cancer

Abstract

Background: To determine the frequency and severity of anemia in non-metastatic breast cancer patients receiving neoadjuvant or adjuvant chemotherapy.

Methods: Cross-sectional study (2018–2023). Hemoglobin (Hb) was analyzed before, during, and after chemotherapy (~6 months). Regimens: dose-dense AC-T (q2 weeks) or standard AC-T (q3 weeks).

Main findings: Hb differed across time (Bonferroni all p < 0.001) and was lowest during therapy. During therapy, dose-dense AC-T had lower mean Hb than standard AC-T (118.2 ± 10.2 vs 123.1 ± 9.8 g/L; Δ = 4.9 g/L; ≈4.0%; t = 2.620; p = 0.010). No significant Hb differences by treatment setting (adjuvant vs neoadjuvant −2.1%; p = 0.312), trastuzumab (−2.6%; p = 0.143), pertuzumab (−2.5%; p = 0.375), surgery type (breast-conserving +1.7% vs mastectomy; p = 0.432), or comorbidities (−2.6%; p = 0.105). Menopausal status (F(2,112)=0.635; p = 0.532), histology (F(3,111)=1.268; p = 0.289), and stage (F(2,112)=0.193; p = 0.825) were not associated with Hb. Anemia prevalence was 46.1%. Cohort profile: 65.2% postmenopausal; 53.9% stage 2; 81.7% adjuvant therapy; 84.3% radical mastectomy; 25.2% trastuzumab; 8.7% pertuzumab. Age did not differ between anemic and non-anemic groups; anemic patients had significantly lower BMI.

Principal conclusion: Hb declines most during therapy; a dose-dense schedule is associated with an additional ≈4% reduction versus standard scheduling, while other evaluated clinical factors did not materially affect Hb. Lower BMI among anemic patients suggests nutritional status as a potential target for supportive care.