Refractory T cell acute lymphoblastic leukemia with unusual karyotype and interesting immunophenotype

Area of Science:

• Hematology
• Cytogenetics
• Flow Cytometry

Background:

• Accurate diagnosis and prognosis of Acute Lymphocytic Leukemia (ALL) rely on integrated karyotype, immunophenotype, and molecular studies.
• These analyses provide critical diagnostic and prognostic information for effective patient management.

Observation:

• A unique case of ALL presented with complex and unusual hypodiploid cytogenetics: 45,XY,i(7q),der(9)t(3;9)(q12;p22),del(12)(p12),:der(18)t(3;18)(p14;q22),-3.
• The karyotype revealed a loss of chromosome 3, a rare finding, and a chromosome 12p deletion, both associated with leukemogenesis.
• Immunophenotype analysis indicated positivity for CD7 and CD10, suggesting T and precursor B cell markers, respectively. T cell receptor gene rearrangement confirmed a T cell lineage.

Findings:

• The observed hypodiploidy and T cell phenotype are recognized indicators of a poor prognosis in ALL.
• The patient's leukemia was refractory to standard chemotherapeutic protocols.
• A notable response was achieved with an unconventional treatment combining high-dose cytarabine (Ara-C), etoposide, and L-asparaginase.

Implications:

• This case highlights the importance of comprehensive cytogenetic and immunophenotypic analysis for diagnosing complex ALL cases.
• The unusual genetic findings and T cell lineage underscore the heterogeneity of ALL.
• The patient's response to an unconventional regimen suggests potential alternative therapeutic strategies for refractory ALL cases with similar profiles.