[Clinical Features and Prognosis of Acute Lymphoblastic Leukemia Children with P2RY8-CRLF2 Gene Rearrangement].

ABSTRACT

OBJECTIVE: To investigate the clinical features and prognostic factors of acute lymphoblastic leukemia (ALL) children with P2RY8-CRLF2 gene rearrangement. METHODS: A total of 108 children with B-cell ALL (B-ALL) were diagnosed and systematically treated according to Chinese Children's Leukemia Group (CCLG) -ALL 2008 in our hospital from January 2016 to December 2016. The 108 patients were divided into two groups according to the result of mutiplex polymerase chain reaction group with P2RY8-CRLF2 gene rearrangement and group without P2RY8-CRLF2 gene rearrangement. The ALL children with P2RY8-CRLF2 gene rearrangement were all treated by CCLG-ALL 2008 high-risk group (HR) regimens, and the ALL children in group without P2RY8-CRLF2 gene rearrangement received different intensity chemotherapy according to clinical risk classification. RESULTS: Five (4 male and 1 female) out of 108 patients with B-ALL had P2RY8-CRLF2 gene rearrangement. In the 5 B-ALL patients with P2RY8-CRLF2 gene rearrangement, the median age of the was 4 (2-6) years old and the median WBC count was 26.2 (2.46-525.1)×109/L. These patients presented different immunophenotype, including 3 cases of common B-ALL and 2 cases of pre B-ALL. Four patients carried a normal karyotype and 1 patient carried 46, XY, der (20) [22]/46, XY[2]. For the children with P2RY8-CRLF2 gene rearrangement, 1 patient (20%) could not achieve complete remission (CR), and minimal residual disease (MRD) of 2 patients (40%) was higher than 1% on day 33 of induction chemotherapy; while in group without P2RY8-CRLF2 gene rearrangement, all the patient achieved CR, and MRD in 6 patients (5.8%) was higher than 1% on day 33 of induction chemotherapy. The 3 year event-free survival (EFS) of ALL children in group with P2RY8-CRLF2 gene rearrangement was significantly lower than that in group without P2RY8-CRLF2 gene rearrangement (60.0%±21.9% vs 85.9%±3.9%) (P<0.05). CONCLUSION: The early treatment response and prognosis of ALL children with P2RY8-CRLF2 gene rearrangement are worse, and more effective protocol is needed for this subtype patients.