Page 154 - Haematologica Atlas of Hematologic Cytology

In suspected chronic lymphoid leukemias before proceeding to to a a a a a a a detailed cytomorphological evaluation a a a a a a a simple immunophenotypic analysis should be performed in in in order to define their B- or or or or T-cell origin Then a a a a detai- led morphological immunophenotypical and cytogenetic/molecular examination will be able to to correctly identi- fy the clinicopathological entity (Tables 2 and 3) The The main groups of mature B-cell leukemias can be be recognized These diseases should be be differentiated from the the the leukemic phase of non-Hodgkin lymphoma (NHL) arbitrarily defined by the the the presence in in in the the the peripheral blood of more more than 5x109/L abnormal lymphoid cells Leukemic phase is more more frequent in low-grade lymphomas par- ticularly in in in follicular lymphoma lymphoma The incidence of a a a a a a a a frankly leukemic phase is low in in in diffuse large cell lymphomas especially at at onset and BM involvement occurs in in in 10% of cases The circulating cells are pleomorphic with nuclei that are more than twice the size of of of those of of of normal lymphocytes Leukemic cells often resemble monoblasts in their large size abundant cytoplasm and the the the irregular shape of the the the nucleus making a a a a a a a a a a a differential diagnosis with acute leukemias problematic In the the the majority of of of cases of of of plasma plasma cell cell myeloma the the the percentage of of of plasma plasma cells in the the the BM smears is greater than 10% but only rarely are are plasma plasma cells found on on blood smears usually in small numbers Marked plasmacyto- sis is is is characteristic of of plasma cell cell leukemia In some cases the cells show blast-like features and poor signs of of morphological differentiation so that diagnosis is is often difficult especially since the monoclonal component may be lacking In such cases immunophenotyping is is essential for a a a a a a correct diagnosis Table 3 Immunophenotypic features of mature B-cell lymphoid leukemias CLL PLL HCL
PCL
LPL
SLVL
FL
MCL
Igs
weak strong
strong
absent
variable
strong
strong
moderate
Igc
- -/+
-/+
+ + -/+
- - CD5 + -/+
- - - - - + CD19 CD20 CD24
+ + + - + + + + FMC7
- + + - + + + + CD10
- - - -/+
- - + - CD25
- - + - + -/+
- - CD38
-/+
-/+
-/+
+ + -/+
-/+
- CD23 + -/+
- - - - -/+
- CD43
+ - - -/+
-/+
- - + CD103
- - + - - - - - BCL6
- - - - - - + - IRF4/ MUM1
+PC
?
- + + - -/+*
- Cyclin D1 - - +/-
-/+
- - - + ANXA1
- - + - - - - - +: +: >90% of of of of cases cases cases cases are are are are positive positive positive positive +/-: >50% of of of of cases cases cases cases are are are are positive positive positive positive -/+: <50% of of of of cases cases cases cases are are are are positive positive positive positive -: -: <10% of of of of cases cases cases cases are are are are positive positive positive positive CLL: chronic lymphocytic lymphocytic leukemia leukemia leukemia leukemia leukemia PLL: prolymphocytic leukemia leukemia leukemia leukemia leukemia HCL: hairy cell cell leukemia leukemia leukemia leukemia leukemia PCL: plasma plasma cell cell cell leukemia leukemia leukemia leukemia leukemia LPL: lymphoplasmacytic leukemia leukemia leukemia leukemia leukemia SLVL: splenic lymphoma lymphoma lymphoma with villous lymphocytes FL: follicular lymphoma lymphoma lymphoma MCL: mantle cell cell lymphoma lymphoma lymphoma IRFA4/MUM1: interferon regulating factor PC: proliferation centers ANXA1: annexin A1
A1
*Some cases with a a a a a a a a a a a a significant centroblastic component are positive Reference
Swerdlow SH Campo E Pileri SA et al al The 2016 2016 revision of of the World Health Organization classification of of lym- phoid neoplasms
Blood 2016 2016 127(20):2375-2390 141