Persistent clonal chromosomal abnormalities in a chronic myeloid leukemia patient

Area of Science:

• Hematology
• Oncology
• Genetics

Background:

• Clonal cytogenetic abnormalities (CCA) in Philadelphia chromosome (Ph)-negative cells are infrequently observed in adult chronic myelogenous leukemia (CML).
• CCA in pediatric CML patients are even rarer, making their study crucial for understanding disease progression and treatment responses.

Observation:

• This report details the case of an 8-year-old boy diagnosed with CML.
• The patient experienced a relapse post-unrelated bone marrow transplantation at age 9 but achieved complete molecular response with imatinib mesylate.
• Remarkably, various CCA, including reciprocal chromosomal translocations in Ph-negative cells, were detected and persisted for over 12 years.

Findings:

• Despite the presence of dysplasia in bone marrow cells, the patient did not develop myelodysplastic syndrome or acute myeloid leukemia.
• The underlying cause for the sustained CCA in this pediatric CML patient remains unidentified.

Implications:

• This case underscores the need for long-term monitoring of pediatric CML patients, particularly those with persistent CCA.
• Further research is warranted to elucidate the mechanisms driving CCA in CML and their clinical significance.