TRBC1 and acute lymphoblastic leukemia: Single staining for TRBC1 only produced spurious TRBC1-dim subsets in 24 of 90 (27%) clinical specimens studied with our clinical T-cell immunophenotyping panels (excluding T-ALL cases and specimens with benign T-cell precursors where CD3-dim/TRBC-dim T-cells are expected) (Fig. 6).