Dynamic Monitoring of Plasma ctDNA for Prognostic Assessment in Patients With B-Cell Non-Hodgkin Lymphoma

Inclusion Criteria: * Age ≥ 18 years and ≤ 75 years. * Histopathologically and immunohistochemically confirmed diagnosis of B-cell non-Hodgkin lymphoma (according to the latest WHO classification). * Presence of at least one evaluable target lesion prior to initial treatment (based on Lugano 2014 criteria). * Availability of feasible tumor tissue samples or fresh biopsy specimens (from initial diagnosis or relapse biopsy) for establishing a personalized sequencing assay (e.g., identification of patient-specific mutations via tumor tissue DNA sequencing for ctDNA tracking). * Planned to receive standard regimen therapy (first-line regimen for treatment-naïve patients, second-line regimen for relapsed/refractory patients). * Eastern Cooperative Oncology Group (ECOG) performance status score of 0-2. * Voluntary participation in this study with written informed consent provided. Exclusion Criteria: * Prior treatment with ≥2 lines of systemic anti-lymphoma therapy. * Presence of other active malignancies * History of myocardial infarction within the past 1 year; presence of New York Heart Association (NYHA) class III or IV congestive heart failure, or a history of NYHA class III or IV congestive heart failure, unless left ventricular ejection fraction (LVEF) is ≥50% on echocardiography (ECHO) screening performed within 1 month prior to study entry. * Hepatic or renal dysfunction: creatinine level ≥176.8 μmol/L (2 mg/dL), transaminase or bilirubin levels \>2 × upper limit of normal (ULN). * Severe hematologic abnormalities: absolute neutrophil count (ANC) \<1 × 10⁹/L, platelet count \<50 × 10⁹/L. * Presence of uncontrolled infection. * Pregnant or breastfeeding women. * Any other condition that the investigator deems inappropriate for participation in this trial.