Persistent Polyclonal B cell Lymphocytosis (PPBL)

Epidemiology and Etiology:

• F > M
• Smokers (98%)

Common sites:

Gross features:

• splenomegaly (10%)

Morphologic features:

• Peripheral blood:
• Binucleated lymphocytes

Immunophenotype:

Marker:	Sensitivity:	Specificity:
CD19
CD5 (neg)
CD23 (neg)
Bcl-2
Kappa & lambda (no restriction)

Molecular features:

• Recurrent chromosomal abnormalities:
• +i(3)(q10) (70%)
• Bcl-2/IGH (polyclonal?)
• chromosomal instability
• premature chromosome condensation (PCC) (39%)

Other features:

• Benign course usually
• Few cases reported to develop MGUS or NHL
• Chronic, stable, persistent, polyclonal lymphocytosis
• Serum IgM increased (polyclonal)
• Asymptomatic or mild nonspecific fatigue

References:

• Leukemia. 2009 February ; 23(2): 419–422. doi:10.1038/leu.2008.208.