Background and purpose: L-asparaginase (L-Asp) is an important drug in the treatment of childhood lymphoid neoplasms at present

but a lot of adverse reactions of L-Asp were observed. Pegasparaginase (PEG-Asp) is available in China in recent years. This study aimed to explore efficacy and side-effect of PEG-Asp as first-line treatment in childhood acute lymphoblastic leukemia (ALL) and lymphoblastic lymphoma (LBL). Methods: A total number of 211 ALL or LBL patients were treated with CCLG 2008 or BFM-90 protocol with PEG-Asp or L-Asp between Apr. 2008 and Mar. 2013; 42 patients

among whom

were 35 ALL patients and 7 LBL patients

were treated with PEG-Asp as first-line treatment; 169 patients were treated with L-Asp as first-line treatment (including 53 patients treated with L-Asp during induction protocol; with PEG-Asp during consolidate protocol). The clinical outcome and adverse reaction of PEG-Asp with L-Asp were observe and compared. Results: There were 35 ALL patients in PEG-Asp first-line treatment group and the complete remission rate after 1 course of PEG-Asp was 97.1%

however

which was 83.3% of high risk ALL patients. The complete remission rate of 7 LBL patients of PEG-Asp firstline treatment group was 57.1%. There was no significant difference between 2 groups (P0.05). Thirty-four patients relapsed including 5 patients of PEG-Asp first-line treatment group

16 patients of L-Asp first-line treatment group and 13 patients treated with L-Asp during induction protocol and with PEG-Asp during consolidate protocol. Thirty-one patients died including 3

18

10 patients in 3 groups respectively. Twenty-two patients died of relapse

4 died without remission

5 died of complications. There was also no significant difference between 2 groups (P0.05). The incidence rates of adverse reactions were 47.6% and 63.3% respectively. Anaphylaxis

liver functions abnormalities

blood coagulation abnormalities

gastrointestinal reaction

hyperglycemia and pancreatitis were common in our patients. The incidence rate of anaphylaxis in PEG-Asp as first-line treatment group was lower than other groups (P=0.03). But there was no significant difference been observed in the incidence of other adverse reaction. Conclusion: The short-term efficacy of PEG-Asp as the first-line treatment in childhood leukemia and lymphoma was satisfactory and the incidence rate of anaphylaxis was lower. However

we will still pay much attention to adverse reaction monitoring of PEG-Asp.