Zanubrutinib, Obinutuzumab, and Lenalidomide (ZGR) in the Treatment of Newly Diagnosed Splenic B-cell Lymphoma With Prominent Nucleoli (SBLPN): A Prospective, Open-label, Single-arm Clinical Trial

Inclusion Criteria:

* Aged 18 to 80 years, male or female
* Histologically or cytologically confirmed SBLPN requiring active treatment;
* No prior systemic therapy for SBLPN received;
* ECOG performance status of 0-2;
* Anticipated life expectancy ≥6 months;
* Laboratory parameters (hematologic and biochemical) meeting the following criteria:
* a. Absolute neutrophil count (ANC) ≥1.0 × 10⁹/L, platelet count ≥50 × 10⁹/L;
* b. Total bilirubin (TBIL) ≤2.0 × upper limit of normal (ULN);
* c. Alanine aminotransferase (ALT) and aspartate aminotransferase (AST) ≤2.5 × ULN;
* d. Creatinine clearance ≥50 mL/min (calculated via Cockcroft-Gault formula or direct measurement).
* Men and women of childbearing potential must agree to use medically approved contraception throughout the study and for 4 weeks after treatment discontinuation;
* Participants must voluntarily enroll in the study and provide written informed consent.

Exclusion Criteria:

* History of central nervous system (CNS) disorders (including CNS lymphoma) diagnosed within 1 year prior to enrollment.
* Other primary malignancies within the past 3 years (excluding non-melanoma skin cancer, curatively treated localized prostate cancer, cervical carcinoma in situ, or squamous intraepithelial lesions on PAP smear).
* Exposure to any investigational drugs, antimicrobial agents, or participation in other interventional clinical trials within 4 weeks prior to enrollment.
* Major surgery (excluding lymph node biopsy) within 14 days before enrollment or anticipated requirement for major surgery during the study.
* Prior use of investigational agents targeting SBLPN.
* Active immunodeficiency, autoimmune diseases, prolonged systemic corticosteroid therapy (\>10 mg/day prednisone equivalent) within 7 days prior to enrollment, or any immunosuppressive therapy.
* Severe hepatic dysfunction (e.g., severe jaundice, hepatic encephalopathy, refractory ascites, hepatorenal syndrome), cachexia, multiorgan failure, or severe renal impairment.
* Clinically significant cardiovascular comorbidities:

New York Heart Association (NYHA) class III/IV heart failure; Myocardial infarction within 6 months prior to enrollment; Uncontrolled arrhythmias (including QTc interval ≥480 ms); Poorly controlled hypertension (systolic ≥150 mmHg/diastolic ≥100 mmHg despite antihypertensives); Unstable angina.

* Bleeding diathesis or coagulation disorders; thrombotic events within 3 months prior to enrollment.
* Hypersensitivity to active ingredients or excipients of the investigational drugs.
* Pregnancy, lactation, or women of childbearing potential unwilling/unable to use contraception.
* Other conditions deemed unsuitable for participation by the investigator (e.g., compromised protocol compliance or safety risks).