Single administration of pegylated filgrastim once per cycle compared to daily filgrastim in patients with primary breast cancer receiving neoadjuvant chemotherapy

Abstract

8206 Background: Neutropenia is common in patients with cancer who receive myelosuppressive chemotherapy (CT) and contributes to therapy induced morbidity and mortality. In regimens with known high rates of febrile neutropenia granulocyte-colony stimulating factors are necessary to reduce therapy induced mortality and to maintain dose intensity. This retrospective clinical evaluation was designed to determine wether a single subcutaneous administration of pegfilgrastim is as safe and effective as daily filgrastim in patients with primary breast cancer. Methods: 90 patients received epidoxorubicin 75 mg/m2 and docetaxel 75 mg/m2 on day 1 plus subcutaneous injection of filgrastim on day 3–10, q 21 (ET + F). Filgrastim was dosed according to body weight with 30 MioIE < 60 kg and 48 MioIE > 60 kg. To the other 20 patients pegfilgrastim was applied on day 2 of the respective therapy regimen subcutaneously and was dosed independently to body weight with 6 mg in all patients. 16 patients received ET + P and the other 4 a combination therapy consisting of oral capecitabine, 1000 mg/m2, twice daily on days 1–14 in combination with the previously mentioned regimen on day 1 of each treatment cycle, q 21 (TEX + P). Since our group has already demonstrated the introduction of capecitabine into the ET regimen does not increase hematological toxicities. Results: Patients received 441 cycles with CT + F and 110 cycles with CT + P. One dose of pegfilgrastim per CT cycle was comparable to daily subcutaneous injection of filgrastim with regard to the occurrence of febrile neutropenia (CT + F: 8/441, 1,8%; CT + P: 1/110, 0,9%) and the need for hospitalization (CT + F: 8/441, 0,45%; CT P: 1/110, 0%). Conclusions: Both treatment groups had an identically adverse event profile. We conclude that single dose application of pegfilgrastim has a good safety profile and offering more convenience to patient and staff in the neoadjuvant treatment for patients with primary breast cancer receiving the ET or TEX regimen respectively. No significant financial relationships to disclose.