Incidence of febrile neutropenia among early-stage breast cancer patients receiving anthracycline-based chemotherapy

The aim of this study was to investigate the incidence of febrile neutropenia (FN) with adjuvant AC (doxorubicin and cyclophosphamide) chemotherapy among Asian early-stage breast cancer (ESBC) patients, to evaluate the impact of FN on chemotherapy delivery, and to identify specific risk factors that would predispose ESBC patients to FN. This was a single-center, observational, retrospective cohort study conducted in Singapore. All ESBC patients who have received the AC regimen as adjuvant chemotherapy between January 2007 and July 2010 were included into the study. Patients did not receive granulocyte colony-stimulating factors (G-CSF) as primary prophylaxis. One hundred and eighty-nine patients and 729 cycles of chemotherapy were analyzed in this study, of which, majority were Chinese (84%). Median age of the patients was 54 years old (IQR 49-58). In total, 26 patients (13.8%) manifested at least one episode of FN, of which 17 patients developed FN during the first cycle of treatment. Patients who manifested FN received similar dose intensities of chemotherapy, compared to those patients who did not manifest FN (100% versus 98%, p = 0.95). After adjusting for age, race, and presence of comorbidities, low body mass index (BMI) (< 23 kg/m(2)) was found to be associated with a higher risk of FN (OR 4.4, 95% CI = 1.65-12.01, p = 0.003). Asian patients are at moderate risk for FN when they receive the AC regimen for treatment of ESBC. Further studies should evaluate the role of G-CSF to reduce the occurrence of FN in Asian patients with low BMI.