Table 3.

Immunophenotype of T-PLL and the most relevant differential diagnosis

Differential diagnosis	Immunophenotype
T-PLL	cyTCL1+ (>90%), CD3+ (>80%), CD4+(60%), CD5+ (100%), CD7+ (>90%), CD8+(15%), CD4+CD8+(25%)
T-ALL	Tdt +, CD1a+
Leukemic PTCL	cyTLC1−
T-cell large granular lymphocytic leukemia	CD8+, CD57+, CD16+
Sézary syndrome	CD7−, CD4+, CD25+
Adult T-cell lymphocytic leukemia	CD4+, CD25+, HTLV1+

Percentage of patients with T-PLL expressing specific markers.¹⁹