Test Details: Acute lymphoblastic leukemia (ALL) is an infrequent aggressive cancer being more common in children. ALL includes B- and T-cell lineage subtypes. T-cell acute lymphoblastic leukemia (T-ALL) accounts for 10–15% of pediatric and 20–25% of adult cases. T-ALL usually has a high degree of malignancy, slow clearance of tumor cells after treatment, and a high early recurrence rate. The significant differences in the pathogenic mechanisms and treatment responses for T-ALL and B-ALL necessitates the use of this test.