[Changes in the variant of acute leukemia]

Area of Science:

• Hematology
• Oncology
• Internal Medicine

Background:

• Acute lymphoblastic leukemia (ALL) is a significant hematologic malignancy.
• Treatment protocols like the VAMP regimen aim for complete remission.
• Extramedullary disease can complicate ALL management.

Observation:

• A female patient achieved complete remission after initial chemotherapy for ALL.
• Over seven years, she experienced recurrent extramedullary relapses (neuroleukemia, breast, mesenteric lymph nodes) with normal blood/marrow findings.
• A terminal relapse showed altered blood/marrow morphology with Sudan and peroxidase-positive blast cells.

Findings:

• The patient's terminal relapse exhibited blast cells with characteristics of myeloblasts.
• This suggests a potential myeloid transformation or diagnostic ambiguity in relapsed ALL.
• Persistent extramedullary disease can occur despite initial treatment success.

Implications:

• This case highlights the complexity of ALL relapse and potential lineage infidelity.
• It underscores the importance of thorough diagnostic evaluation, including immunophenotyping, in relapsed hematologic malignancies.
• Understanding mechanisms of extramedullary relapse and treatment resistance is crucial for improving patient outcomes.