Clinical Study of Thiopegfilgrastim for Preventing Bone Marrow Suppression in Thoracic Tumor Chemoradiotherapy

Inclusion Criteria: * 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 * Signed informed consent; willing and able to comply with protocol-mandated visits * The patient is indicated for concurrent chemoradiotherapy and is currently/receiving or will receive a high-risk chemotherapy regimen for febrile neutropenia (FN risk ≥20%), or is currently/receiving or will receive an intermediate-risk chemotherapy regimen for FN (FN risk 10%\~20%) with additional FN risk factors. Exclusion Criteria: * 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