[A collaborative study on children with mature B-cell non-Hodgkin's lymphoma in China].

OBJECTIVE: This study aimed to evaluate the efficacy of the CCCG-B-NHL 2010 protocol in children with mature B-cell non-Hodgkin's lymphoma (B-NHL) in China retrospectively.

METHOD: Eight tertiary referral centers for childhood cancer participated in this study. From April 2009 to March 2012, 104 patients below 18 years with newly diagnosed, untreated B-NHL or mature B cell acute lymphoblastic leukemia (B-ALL) were enrolled. Six patients refused further staging work-up and treatment due to the expense were excluded. Diagnostic slides were not centrally reviewed in this retrospective study. Twenty-three of 104 patients got rituximab therapy during the treatment.

RESULT: Of the 104 eligible patients (79 boys and 25 girls), the median age was 6.1 years (range 1.8-15.1 years). Two patients (1.9%) had stage I disease, 22 (21.2%) had stage II, 65 (62.5%) had stage III, 9 (8.6%) had stage IV, and 6 (5.8%) had B-ALL. At a median follow-up of 27.9 months (range 4.2-51.5 months), the 2-year probability of event-free survival (EFS) was (76.0 ± 4.3)% in all patients. The 2-year EFS was 100%, (93.3 ± 6.4) %, (75.1 ± 5.4) % and (52.5 ± 13.1) % for patients with stage I, II, III and IV/B-ALL, respectively (P = 0.03). There was no significant difference in EFS between patients treated with chemotherapy only and those with chemotherapy combined with rituximab [(76.1 ± 4.8)% vs. (75.9 ± 9.6)%, P > 0.05]. The 2-year EFS was (84.5 ± 4.8)%, (70.6 ± 11.1)% and (58.0 ± 10.1)% for patients with LDH < 2 times the institutional upper limit of normal (2 times NL), 2-4 times NL and > 4 times NL, respectively (P = 0.02). Only one patient (1%, 1/104) died of treatment-related complications. Six patients refused treatment during therapy. Including the 6 cases who refused to receive further staging diagnostic workup, the abandonment rate for B-NHL/B-ALL was 10.9% (12/110).

CONCLUSION: The EFS rate in this study was much lower in patients with advanced disease (LDH > 4 times NL, stage IV and B-ALL) than that of series conducted in medically developed countries. Establishment of strategies to improve survival in patient with advanced disease is the priorities in our following study.