This is a prospective observational study designed to observe and evaluate the safety and efficacy of mecapegfilgrastim in the treatment of moderate-to-severe myelosuppression associated with concurrent chemoradiotherapy. The project will provide more robust evidence-based medical support for the use of long-acting granulocyte-stimulating agents in patients undergoing concurrent chemoradiotherapy.
Aged 18-75 years at the time of giving informed consent， both sexes eligible
Histologically or cytologically confirmed thoracic tumor (esophageal or lung cancer)
Investigator judges the patient suitable for treatment with mecapegfilgrastim injection or leucogen tablets
Expected survival > 3 months
Pregnant or lactating women
Known hypersensitivity to mecapegfilgrastim, pegylated or non-pegylated rhG-CSF, or any E. coli-derived product
Any severe comorbidity that, in the investigator's opinion, compromises patient safety or ability to complete the study
Any other condition that, in the investigator's judgment, could interfere with study conduct or interpretation of results