Background: On the whole, most European and international guidelines recommend prophylactic use of granulocyte-colony stimulating factors (G-CSFs) when the risk of chemotherapy-induced febrile neutropenia (FN) in cancer patients exceeds 20%. In patients treated with intermediate-risk chemotherapy regimens the recent EORTC guidelines recommend to consider supplementary patient-related adverse risk factors such as elderly age (≥ 65 years) prior to administrating each cycle of chemotherapy. The primary objective of our study is to describe the most important FN risk factors that underlie the use of pegfilgrastim PP in daily practice in the Czech Republic; secondary endpoints include FN incidence, chemotherapy dose intensity, anti-infective agents administration, hospitalization length and safety of chemotherapy regimens. Patients and methods: This prospective, multicenter, non-interventional study enrolled patients receiving a chemotherapy with high FN risk (≥ 20% according to EORTC guidelines) based on investigators` assessment. Results: Data were collected on a total of 333 patients treated for breast cancer (69%), lymphoma (20%), ovarian (5%), lung (4%) and testicular cancer (1%). The most frequent indications for G-CSF prophylaxis were myelotoxic chemotherapy regimen (96%), elderly age (36%), advanced stage disease (35%), female gender (30%), cancer type (15%) and previous FN episode (12%). The overall FN incidence was 3% in patients receiving primary pegfilgrastim prophylaxis (n = 210) and 12% in patients with no pegfilgrastim PP (n = 123). Conclusion: The myelotoxicity of a chemotherapeutic regimen was the most significant FN risk factor identified by the inquired physicians. The second most compelling FN risk factor was elderly age and advanced stage disease. FN incidence in patients who received pegfilgrastim PP was relatively low in comparison to the commonly expected FN incidence in a population of patients receiving a chemotherapy regimen with high risk of FN.