P5-18-09: The Incidence of Febrile Neutropenia in the First Course of Adjuvant Chemotherapy with Docetaxel/Cyclophosphamide with or without Pegfilgrastim.

Abstract

Abstract Background In our original doxorubicin-cyclophosphamide/docetaxel-cyclophosphamide (AC/TC) adjuvant study (JCO 27: 1177–1183, 2009), we reported an incidence of febrile neutropenia (FN) of 5% (8% in women ≥65 years) with the TC regimen without prophylactic WBC growth factors but with a recommendation for prophylactic antibiotics. There is a paucity of data on the incidence of FN with the TC regimen aside from this clinical trial. Because we have been conducting a randomized adjuvant study of TC compared to other regimens, we used this opportunity to analyze the incidence of FN during the first course of chemotherapy with TC in the first cohort of randomized patients (US Oncology Network study 06090). The prophylactic use of WBC growth factors was at the investigator's discretion. Patients and Methods The study included 1298 patients entered between May 2007 and May 2009. Of these, 649 were included in the TC arm. Median age was 54 years (range 27–71), 75.5% were Caucasian, 561 (86.4%) were in PS 0 at baseline, and about half were node negative. Eight patients did not receive study treatment for various reasons. Among the 641 patients who received TC; 213 (33.3%) received pegfilgrastim, 48 (7.5%) received filgrastim and were not included in this analysis, and 380 (59.2%) patients did not receive either during the first cycle. Thus, this analysis focused on 593 women who did or did not receive prophylactic pegfilgrastim in cycle 1. Results: All patients with a reported adverse event of FN or with a reported AE of fever with some degree of neutropenia (in order to capture all possible cases of FN) during the first cycle of TC were identified [Table 1]. FN and fever + neutropenia occurred in a total of 6 (2.8%) patients who received pegfilgrastim and 36 (9.5%) patients who did not. A comparison of age, race, performance status and stage of disease between these 2 groups revealed that they were similar. The 213 patients who received pegfilgrastim were slightly older (median 56 years, range 27–71) compared to those who did not (median 53 years, range 30–71). During all 6 cycles, 41 patients reported FN, and 30 (73%) of these patients experienced FN during cycle 1. Conclusion: Among 593 women who received TC as adjuvant chemotherapy, the incidence of FN during the first cycle was under 10% whether or not the patients received prophylactic pegfilgrastim. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-18-09.