[Rituximab combined with intensive immunochemotherapy for sporadic adult Burkitt lymphoma: efficacy and prognosis...

Objective: To explore the therapeutic efficacy and prognostic factors of combined rituximab and intensive chemotherapy for sporadic adult Burkitt lymphoma (BL) . Methods: This retrospective study examined the clinical and survival data of 30 patients newly diagnosed with BL between July 2011 and February 2023 at the Blood Diseases Hospital. Kaplan-Meier method was used for survival analysis, and the log-rank test was used for univariate analysis of prognostic factors. Results: The median age of the 30 patients was 43 years (24 - 66 years), and the male to female ratio was 3: 2. Extranodal invasion was present in 80% of the patients, with involvement of the bone marrow in 53.3% and central nervous system in 10.0%. The Ann Arbor stage was Ⅲ and Ⅳ in 86.7%. According to the number of Burkitt Lymphoma International Prognostic Index (BL-IPI) risk factors, patients were classified as low risk (0) in 20.0%, intermediate risk (1) in 43.3%, and high risk (≥2) in 36.7%. All patients were treated with an induction regimen of rituximab combined with intensive chemotherapy, with objective and complete response rates of 80.0% and 76.7%, respectively. The median follow-up was 49 months (6-153 months), and the 5-year progression-free survival (PFS) and overall survival (OS) rates were both (76.7±7.7) %. All patients with limited stage (n=4) achieved continuous complete remission (CCR). Patients who had high risk, advanced stage sensitive to induction therapy (n=10) sequentially received first-line autologous hematopoietic stem cell transplantation (auto-HSCT) as consolidation therapy; 9 patients achieved CCR, whereas 1 patient with central nervous system invasion developed early disease progression and died. The BL-IPI low, intermediate, and high risk groups had respective 5-year PFS rates of (83.3±15.2) %, 100.0%, and (45.5±15.0) % (P=0.0069) and OS rates of (83.3±15.2) %, 100.0%, and (45.5±15.0) % (P=0.0075). The main adverse effects of induction therapy were myelosuppression and secondary infections, which were effectively managed by appropriate symptomatic treatment. Univariate analysis demonstrated that worse PFS was associated with BL-IPI score ≥2 (HR=4.90, 95% CI 1.02-23.45, P=0.0329) ; extranodal invasion at ≥2 sites (HR=12.62, 95% CI 2.59-61.62, P=0.0021) ; and failure to achieve first complete response (CR1) after induction therapy (HR=31.86, 95% CI 4.19-242.20, P<0.0001) . Conclusions: Intensive immunochemotherapy regimens were effective and well-tolerated by adult patients with highly aggressive BL. Treatment efficacy was ideal in patients with limited-stage disease, whereas prognosis was unsatisfactory in patients with high-risk BL-IPI. Sequential first-line auto-HSCT consolidation therapy may further improve outcomes in patients with high-risk advanced-stage disease who are sensitive to induction therapy. BL-IPI score ≥2, extranodal invasion at ≥2 sites, and failure to achieve CR1 after induction therapy were adverse prognostic factors in adult patients with BL.