Chronic Lymphocytic Leukemia (CLL)/ Small Lymphocytic
Lymphoma (SLL)
Clinical criteria:
Absolute clonal lymphocytes >5000/uLQ
MC leukemia of adults in the Western world.
Median age at diagnosis is 60 years; M:F = 2 : 1
MC mutation–Del 13q.
Cell of origin–Naive B cell.
Peripheral Smear:
Small round lymphocytes with scant cytoplasm
CONVENT girl appearance)Q
Occasional cells have distorted outline called smudge
cellsQ
Rarely Warm type AIHA may develop showing SpherocytesQ
Morphology of Lymph nodes:
Diffusely effacedQ by an infiltrate of predominantly small
lymphocytes (6- 12μm) between which lies larger activated
lymphocytes- proliferation centersQ (pathognomonic
for CLL/SLL), which contain mitotically active cells.
Overall CLL has low mitotic rateQ exc in proliferative center
Immunophenotyping (Diagnosis of choice):
Dim Surface Ig (usually IgM or IgM and IgD)Q
Pan B-cell markers CD19 + and CD20+Q
CD23+ and CD5+Q