Neutropenia occurrence and predictors of reduced chemotherapy delivery: results from the INC-EU prospective observational European neutropenia study

Goals of work  Neutropenia is a life-threatening, dose-limiting toxicity of many chemotherapy regimens. The goals of this study were to assess the incidence and risk of chemotherapy-induced neutropenia, febrile neutropenia (FN) and dose limitations in breast cancer and lymphoma patients undergoing chemotherapy in Europe. Patients and methods  Four hundred forty-four breast cancer and 305 lymphoma patients undergoing chemotherapy at 66 practices in five European countries participated in this prospective, observational study. Predictors of impaired chemotherapy delivery were investigated using a logistic regression model. Main results  In breast cancer, FN incidence was low (6%); however, grade 4 neutropenia was frequent (34%). Lymphoma patients experienced higher incidences of FN (non-Hodgkin lymphoma (NHL) 22%; Hodgkin lymphoma (HL) 15%) and grade 4 neutropenia (NHL 54%; HL 40%). For both diseases, FN and grade 4 neutropenia were associated with low relative dose intensity (RDI). Multivariate regression models indicated that first cycle FN, age ≥ 65 years and Eastern Co-operative Oncology Group > 1 were associated with low RDI in breast cancer and lymphoma, while colony-stimulating factor (CSF) primary prophylaxis appeared to be protective in lymphoma only. Primary CSF prophylaxis was provided to 9% of breast cancer, 28% of NHL and 19% of HL patients. Conclusions  Neutropenia and low RDI remain serious problems in both breast cancer and lymphoma populations undergoing chemotherapy. Several risk factors which can trigger reduced chemotherapy delivery were identified. These results can support physicians in identifying patients most at risk of receiving impaired chemotherapy delivery who would benefit from suitable preventive measures.