Neutrophil count is not associated with infection episodes in breast cancer patients treated with anthracycline-based chemotherapy

The aim was to evaluate the impact of anthracycline-based chemotherapy on neutrophil count and infections in breast cancer women. The medical records of patients were retrospectively and prospectively reviewed (8-year period). Patients were grouped according to anthracyclines at different doses: (1) Scheme 1 (n = 56, 224 courses): 50-60 mg/m(2); and (2) Scheme 2 (n = 25, 100 courses): 65-75 mg/m(2), associated to cyclophosphamide and 5-fluorouracil, at 21-day intervals between courses. Neutrophil count was performed on diagnosis and 48-72 h before each chemotherapy course. Patients were followed up for neutrophil count and infection episodes for three consecutive courses. Multivariate analysis was used to determine independent factors for infection. After the first course, neutrophil count was reduced than baseline (P < 0.001) and maintained during the subsequent courses, without differences between courses or groups. There were 49 infection episodes (63.2% urinary, 18.4% neutropenic fever and 18.4% diverses), mainly between course 1-2 (39%) and course 3-4 (38%) of chemotherapy. Patients evaluated as presenting or not with infection episodes did not differ in neutrophil count. The number of chemotherapy courses (P < 0.05), but not age, neutrophil count or chemotherapy regimen, was associated with infection. We concluded that progressive chemotherapy, but not neutrophil count, was an independent factor for infection.