This clinical study is a multiple center, registering and real-world conditional research. The breast cancer patients planning for chemotherapy evaluated with medium-high risk of febrile neutropenia (FN) are recruited, receiving the first level prophylactic use of PEG-rhG-CSF or the second level prophylactic use of PEG-rhG-CSF in at least two cycles of chemotherapy according to real-world clinical judgement and choice by physicians in local cancer center. Comparing real conditional-FN rate, FN-caused hospitalization rate and antibiotic use rate, direct/indirect medical cost.

The breast cancer patients planning for neo-adjuvant/adjuvant chemotherapy evaluated with medium-high risk of febrile neutropenia (FN) according to NCCN and ASCO guideline are recruited, receiving the first level prophylactic use of PEG-rhG-CSF or the second level prophylactic use of PEG-rhG-CSF according to real-world clinical judgement and choice by physicians in local cancer center for at least two cycles of chemotherapy. The primary outcome is FN rate, the second outcomes are rate of 3-4 grade decrease of ANC, FN-caused hospitalization, FN-caused antibiotic use rate, rate of reduction of chemotherapy dose, delay of chemotherapy, safety and pharmacoeconomics.

Inclusion Criteria:

1. provision of informed consent
2. stage I-III, invasive breast cancer
3. accept at least 4 cycles of chemotherapy
4. ECOG score 0-2
5. with medium-high risk of FN according to researchers

Exclusion Criteria:

1. accepted stem cell or bone marrow transplant
2. undergoing any other clinical trial
3. uncontrolled infection, temperature≥38℃
4. per-week scheme chemotherapy
5. concurrent with radiotherapy
6. allergic conditions
7. sever organ dysfunction
8. uncontrolled diabetes

Patients who undergoing chemotherapy given by prophylactic PEG-rhG-CSF using for preventing FN.