Background: Despite significant advancements in breast cancer treatment with targeted therapy and immunotherapy, chemotherapy remains a crucial component across all stages. Anthracycline-based chemotherapy, while commonly administered, can lead to severe and potentially fatal complications such as febrile neutropenia.
Objectives: This study aimed to investigate the prevalence and predictive factors for developing neutropenia in patients with breast cancer undergoing an anthracycline-based chemotherapy regimen.
Methods: A retrospective case-control study was conducted at the Surin Hospital Cancer Center from January 2020 to December 2022. It focused on patients diagnosed with breast cancer and treated with anthracycline-based chemotherapy, specifically the doxorubicin-cyclophosphamide regimen (AC). Prognostic factors were analyzed using a flexible parametric regression model, employing univariate and multivariate analyses.
Results: A total of 174 eligible patients with confirmed breast cancer who received AC regimen chemotherapy were included; 99.4% were predominantly female, with 21.7% being over 65 and nearly 40% having at least one other health condition. Neutropenia, characterized by a neutrophil count of less than 500 cells/mm3, was observed among 18% of patients. Of these, 4% developed febrile neutropenia, resulting in two deaths. A multivariate analysis identified two factors, age of 65 years or older (adjusted OR=3.18; 95% CI 1.122-9.013; p=0.029) and an initial absolute neutrophil count less than 3,000 cells/mm3 (adjusted OR=2.73; 95% CI 1.032-7.204; p=0.043), as independent predictors of neutropenia. Interestingly, the severity of neutropenia did not significantly differ between patients with or without additional health conditions or varying nutritional statuses.
Conclusion: As anticipated, a significant prevalence of neutropenia was observed among individuals with breast cancer, underscoring the critical importance of age and initial neutrophil count in predicting the severity of neutropenic incidents. These findings offer valuable insights for tailoring treatment strategies and optimizing patient care in this clinical context.