Haematological Alterations According to Treatment Status among Nigerian Women with Breast Cancer

Background: Breast cancer and its treatment may alter erythropoiesis, leukocyte distribution and platelet characteristics. Evidence describing these changes among Nigerian women remains limited, particularly in studies that distinguish newly diagnosed patients from treatment-exposed patients. Aim: To determine haematological alterations according to treatment status among Nigerian women with breast cancer. Materials and Methods: This case-control study analysed 120 women in Port Harcourt, Nigeria: 40 treatment-exposed breast cancer patients, 40 newly diagnosed treatment-naive breast cancer patients and 40 apparently healthy controls. EDTA-anticoagulated whole blood was analysed using an automated haematology analyser. Results were summarised as mean ± standard error of the mean (SEM). Full blood count, differential leukocyte parameters and platelet indices were compared using one-way analysis of variance (ANOVA). Significant omnibus results were followed by Tukey’s honestly significant difference comparisons. Statistical significance was set at p < 0.05. Results: Treatment-exposed patients had lower mean haemoglobin (11.04 ± 0.39 g/dL) than newly diagnosed patients (11.56 ± 0.26 g/dL) and controls (11.69 ± 0.13 g/dL; F = 10.7118, p < 0.0001). Significant group differences also occurred in MCV (F = 6.5726, p = 0.0020), MCH (F = 15.0127, p < 0.0001), MCHC (F = 13.7059, p < 0.0001), RDW-CV (F = 30.2256, p < 0.0001) and RDW-SD (F = 25.1891, p < 0.0001). Treatment-exposed patients had the highest neutrophil percentage (63.70 ± 2.32%; F = 22.8691, p < 0.0001) and lowest lymphocyte percentage (27.70 ± 2.30%; F = 34.1758, p < 0.0001). Monocyte percentage differed across groups (F = 6.0390, p = 0.0032); between-group tests for basophil percentage were not reported. Platelet count was similar across groups (F = 0.2378, p = 0.7887), whereas PDW differed significantly (F = 12.5106, p < 0.0001). The reported group superscripts identify differences involving treatment-exposed patients for several erythrocyte and leukocyte measures. Conclusion: Treatment-exposed women demonstrated the most pronounced erythrocyte and leukocyte-distribution abnormalities. The findings support routine full blood count monitoring before and during breast cancer treatment, but the cross-sectional design does not establish that treatment caused the abnormalities.