12th Congress of the European Hematology ... - Haematologica

12 th Congress of the European Hematology Association
prevalent in NHL tissues (17 cases; 10%); Chlamydia pneumoniae and trachomatis
DNA was detected in 3 cases (2%) (p=0.001). Cp DNA was
present in 5 (7%) out of 74 controls; it was detected in 15 (11%) out of
141 extranodal lymphomas and in 2 (6%) of 31 nodal lymphomas
(p=0.48) (Table 1). Among extranodal lymphomas, the prevalence of Cp
DNA was 10% and 11% respectively for B- and T-cell lymphomas.
According to the histotype of extranodal B-cell lymphomas, Cp DNA
was present in 4 (7%) of the 56 marginal zone B-cell lymphomas (MZL)
and in 9 (15%) of 73 diffuse large B-cell lymphomas (DLBCL) (p=0.33).
Cp infection was not randomly distributed among extranodal B-cell
lymphomas: it was detected in 6 (25)% of cutaneous lymphomas and
in 18% of DLBCL arising in the Waldeyer’s ring, while it was rarely
detected in gastrointestinal sites. Conclusions. This is the largest study
revealing that Cp-related lymphomas may occur outside the ocular
adnexae; these lymphomas may arise in the skin and Waldeyer’s ring,
two extranodal sites considered as first-barrier to antigen exposure. This
finding may have obvious clinical implications, in view of the encouraging
results offered by Cp-eradicating therapy with doxycycline in the
treatment of OAL. These figures should be considered in view of the
possible differences in the prevalence rate of Cp infection in OAL among
different geographical regions reported in the literature.
Table 1.
0292
SPLENIC LYMPHOMA WITH VILLOUS LYMPHOCYTES (VL>20%) CONSTITUTES A VARIANT
OS SPLENIC MARGINAL ZONE LYMPHOMA WITH DISTINCT CLINICO-PATHOLOGICAL AND
MOLECULAR FEATURES
M. Baseggio, A. Traverse-Glehen, F. Berger, E. Callet-Bauchu,
M. Ffrench, D. Morel, C. Thieblemont, G. Salles, B. Coiffier, P. Felman
Centre Hospitalier Lyon-Sud, Pierre Benite, France
Splenic marginal zone lymphoma (SMZL) presents some degree of
molecular heterogeneity, which suggests the coexistence of different
diseases. Especially splenic lymphoma with villous lymphocytes (SLVL)
defined at the beginning by hematologists on blood films and incorporated
in WHO classification as the leukaemic form of almost all SMZL,
could play a role in this heterogeneity. In our experience, the aspect and
proportion of villous lymphoid cells (VL) in blood may be quite variable,
and typical VL are often lacking or rare indeed in SMZL. Thus, with the
aim to define more homogeneous entities, we selected among our files
of SMZL, 37 cases displaying more than 20% of typical VL and for
which cytogenetic and molecular data were available, and were compared
them to a control group of classical non-villous SMZL. Patients
presented a male predominance (sex ratio: 1.76) with a median age of
76 years old, a moderate lymphocytosis (from 4.3 G/L to 25.5 G/L) with
splenomegaly (97%) without lymphadenopathy (5%) or pancytopenia
(32% anemia, 15% thrombocytopenia, 3% neutropenia). Immunophenotypically,
the monoclonal B cells expressed IgM (20%), IgG (20%),
IgM+G (22%) or IgM+D (30%), CD76 (86%), CD11c (97%), and usually
lack CD25 (one positive case) or CD5 (5 faintly positive cases). Interstingly
CD103 and CD123, known as markers of hairy-cell leukemia
(HCL), were expressed in 13 of 34 and in 3 of 19 available cases, respectively.
Besides, the fluorescence intensity (RFI) of the CD11c and CD22
106 | haematologica/the hematology journal | 2007; 92(s1)
appeared different in SLVL, SMZL and HCL. On VL, the CD11c and
CD22 expression was moderate (RFI CD11c=40 and CD22 RFI=138),
whereas in SMZL the CD11c and CD22 staining was lower (RFI
CD11c=15 and CD22 RFI=62) and in HCL the CD11c and CD22 staining
was very strong (RFI CD11c=211 and CD22 RFI=268) (p