Clinical Report: Pediatric Case of Ph-Positive T-ALL Progressing to CML

Background

Philadelphia chromosome-positive T-ALL is a rare condition that poses significant diagnostic challenges, particularly in pediatric patients. Accurate differentiation between de novo T-ALL and T-lymphoid blast-phase CML is crucial for appropriate therapeutic management.

Data Highlights

The patient achieved complete remission following induction chemotherapy with VICP and imatinib. After discontinuing imatinib for 18 months, he later developed CML.

Key Findings

• The patient was initially diagnosed with de novo Ph-positive T-ALL based on clinical presentation and cytogenetic analysis.
• Flow cytometric immunophenotyping confirmed T-ALL with a significant population of T-lymphoblasts.
• Conventional cytogenetic analysis revealed a karyotype consistent with Ph-positive leukemia.
• Discontinuation of imatinib led to the development of CML.

Clinical Implications

Clinicians should be aware of the potential for misdiagnosis between de novo Ph-positive T-ALL and T-lymphoid BP-CML.

Conclusion

This case illustrates the complexities in diagnosing Ph-positive leukemias in pediatric patients.

Related Resources & Content

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3. Frontiers in Pediatrics, 2026 -- Case Report: Acute myeloid leukemia with mixed immunophenotypic features and TCF3::ZNF384 fusion in a pediatric patient with CNS involvement: a diagnostic and therapeutic challenge
4. 2025 European LeukemiaNet recommendations for the management of chronic myeloid leukemia | Leukemia
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