Impact of primary pegfilgrastim prophylaxis on relative dose intensity in neoadjuvant/adjuvant FEC-100 chemotherapy

Abstract

Background/Aim: This study aimed was to clarify the impact of pegfilgrastim (PEG) 3.6 mg primary prophylaxis of febrile neutropenia (FN) on the average relative dose intensity (ARDI) of neoadjuvant/adjuvant FEC-100 for breast cancer. Materials and Methods: This retrospective, single-centre cohort study including 296 patients who received FEC-100 compared PEG and non-PEG groups. The PEG group received PEG 3.6 mg as a single subcutaneous injection in each study cycle. The primary endpoint was the ARDI of FEC-100. The secondary endpoints were patient percentage of ARDI≥85%, factors associated with ARDI≥85%, and reasons for reduced ARDI. Results: The PEG group showed significantly higher mean ARDI (95.6% versus 90.7%, p<0.001) and patient percentage of ARDI≥85% (93.0% versus 79.9%, p=0.001). PEG was significantly associated with ARDI≥85% (p=0.009). Neutropenia and FN, the main reasons for reduced ARDI, were significantly lower in the PEG group (p<0.05). Conclusion: Primary PEG 3.6 mg prophylaxis increased the ARDI of FEC-100.