Prethymic Cytoplasmic CD3 Negative Acute Lymphoblastic Leukemia or Acute Undifferentiated Leukemia: A Case Report

Table 1

T-ALL EGIL classification of T lineage acute lymphoblastic leukemia (T-ALL) modified by Szczepanski et al. [2].

MARKERS	Pro-T-ALL; (EGIL T-I)	Immature thymocyte; (EGIL T-II)	Common thymocytic T-ALL mCD3-(Cortical T-ALL, EGIL T-III)	Common thymocytic T-ALL mCD3+ (Cortical T-ALL, EGIL T-III)	Mature T-ALL (EGIL T-IV)
TdT	++	++	++	++	++
HLA-DR	+	−	−	−	−
CD34	+	−	−	−	−
CD1a	−	−	++	++	−
CD2	+	++	++	++	++
cyCD3	++	++	++	++	++
CD5	−	++	++	++	++
CD7	++	++	++	++	++
CD4−CD8−	++	+	−	−	−
CD4+CD8−	−	+/−	+/−	+/−	+
CD4−CD8+	−	+/−	+/−	+/−	+/−
CD4+CD8+	−	−	+	+	+/−
mCD3	−	−	−	++	++
TcR𝛼𝛽	−	−	−	60–70%	60–70%
TcR𝛾𝛿	−	−	−	30–40%	30–40%

<10% of the leukaemias are positive; +/−: 10–25% of the leukaemias are positive; +: 25–75% of the leukaemias are positive; ++: >75% of the leukaemias are positive.