Clinical and molecular characterization of early T-cell precursor acute lymphoblastic leukemia: Two cases report and literature review.

RATIONALE: Early T-cell precursor acute lymphoblastic leukemia (ETP-ALL) is a small subtype of T-cell acute lymphoblastic leukemia with a typical immune-phenotype: lack of T-lineage cell surface markers CD1a and CD8 expression, weak or absent CD5 expression, at least one of the myeloid or hematopoietic stem cell markers. It is characterized by high rate of induction failure and the effective unified treatment strategies are still indeterminate. We present 2 ETP-ALL cases.

PATIENT CONCERNS: A 42-year-old man presented with abnormal hemogram for 4 months, intermittent fever for 2 months and cough for 1 week. A 27-year-old woman was admitted to the hospital for a fever and headache for that had persisted for 1 week.

DIAGNOSIS: The peripheral blood examination, the bone marrow aspiration and flow cytometry for both patients revealed ETP-ALL.

INTERVENTIONS: Both cases accepted chemotherapy including cytarabine.

OUTCOMES: In case one, the patient reached complete hematological remission with negative minimal residual detected by flow cytometry after the first circle of chemotherapy. In case 2, the patient received complete remission after the second circle of chemotherapy with high doses of cytarabine.

LESSONS: The application of the high-dose cytarabine in induction chemotherapy of ETP-ALL can bring better outcome. ETP-ALL with myeloid features may benefit from therapies used in myeloid malignancies.