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[Clinical Characteristics and Treatment Efficacy of Children with SIL/TAL1 Positive T-Cell Acute Lymphoblastic
Xiao Liu1, Wei-Jing Li1, Xiao-Xi Zhao1
1Hematologic Oncology Center, Beijing Key Laboratory of Pediatric Hematology and Oncology; Key Laboratory of Major Diseases in Children, Ministry of Education; National Key Discipline of Pediatrics; Beijing Children's Hospital, Capital Medical University, Beijing 100045, China.
Insights
Children with SIL-TAL1 positive T-cell acute lymphoblastic leukemia (T-ALL) show higher white blood cell counts but similar treatment outcomes. The BCH-2003 protocol may be more effective for this T-ALL subtype.
Area of Science:
- Pediatric Oncology
- Hematology
- Molecular Diagnostics
Background:
- T-cell acute lymphoblastic leukemia (T-ALL) is an aggressive blood cancer in children.
- The SIL-TAL1 fusion gene is a specific genetic marker found in a subset of T-ALL cases.
- Understanding the clinical impact of SIL-TAL1 is crucial for optimizing treatment strategies.
Purpose of the Study:
- To analyze the clinical characteristics, treatment responses, and prognosis of pediatric T-ALL patients with the SIL-TAL1 fusion gene.
- To compare outcomes between SIL-TAL1 positive and negative T-ALL cases.
- To evaluate the effectiveness of different treatment protocols (BCH-2003 vs. CCLG-2008) in SIL-TAL1 positive T-ALL.
Main Methods:
- Retrospective analysis of 101 pediatric T-ALL cases treated between 2005 and 2012.
- Comparison of clinical features, early treatment response, and minimal residual disease (MRD) levels between SIL-TAL1 positive and negative groups.
- Assessment of event-free survival (EFS) and relapse-free survival (RFS), and comparison of treatment protocol efficacy.
Main Results:
- SIL-TAL1 fusion gene was detected in 21.9% of T-ALL cases.
- SIL-TAL1 positive T-ALL cases presented with significantly higher white blood cell (WBC) counts at diagnosis.
- No significant differences in overall survival (EFS, RFS) were observed between SIL-TAL1 positive and negative groups, though higher MRD levels were noted before consolidation therapy in the positive group.
- The BCH-2003 protocol showed a significantly lower risk profile compared to the CCLG-2008 protocol for SIL-TAL1 positive T-ALL.
Conclusions:
- Despite higher WBC counts, SIL-TAL1 positive T-ALL exhibits similar overall treatment efficacy compared to SIL-TAL1 negative T-ALL.
- Children with SIL-TAL1 positive T-ALL might respond less favorably to early intensive therapy.
- The BCH-2003 treatment protocol appears more suitable for managing pediatric T-ALL with the SIL-TAL1 fusion gene.
Objective:
To investigate the clinical features, treatment and prognosis of children with SIL-TAL1 fusion gene positive T-cell acute lymphoblastic leukemia (T-ALL).
Methods:
The data of 101 children with T-ALL were collected from April 2005 to November 2012 in Beijing Children's Hospital. The common clinical features, early treatment response, minimal residual disease (MRD), event-free survival (EFS) and relapse-free survival (RFS) were compared between children with SIL-TAL1 positive and negative T-ALL. The treatment efficacy in children with SIL-TAL1 positive T-ALL was compared between BCH-2003 and CCLG-2008 protocol.
Results:
Out of 101 cases, 22 cases (21.9%) of T-ALL carried SIL-TAL1 fusion gene. The distribution of sex, age, response to prednisone and central nervous system (CNS) involvement were no significant different at diagnosis between SIL-TAL1 positive and negetive patients. However, the WBC count in SIL-TAL1 positive cases were significantly higher than that of SIL-TAL1 negative cases at diagnosis (P<0.05). Additionally, MRD levels were not significantly different between children with SIL-TAL1 positive or negative T-ALL at 3 time points including: after the remission induction therapy, before delayed intensive therapy II and before maintenance therapy. However, the number of cases with high MRD levels before consolidation therapy were more in SIL-TAL1 positive group than that in SIL-TAL1 negative group (P<0.05). The cases with high MRD levels before delayed intensive therapy I was more in SIL-TAL1 negative group than that in the SIL-TAL1 positive group (P>0.05). Besides, there were no significant differences in 5-year EFS and RFS between the two groups. The risk of 22 children with SIL-TAL1 positive acute T-ALL was again stratified according to the typing stemdard in CCLG-2008 protocol, as a result, the risk in BCH-2003 group (10 cases) was significantly higher than that in BCH-2008 group (12 cases) (P<0.05), but no significant difference was found in common clinical features, early treatment response, MRD levels and treatment efficacy.
Conclusions:
Although WBC level was significantly higher in SIL-TAL1 positive group than that in SIL-TAL1 negative group, the treatment efficacy in SIL-TAL1 positive group was similar to SIL-TAL1 negative group. Meanwhile, the children with SIL-TAL1+ T-ALL may respond poorly to early intensive therapy, the BCH-2003 protocol may be more suitable for the patients with this subtype of leukemia.
