Absence of TCL1A expression is a useful diagnostic feature in splenic marginal zone lymphoma.
Splenic marginal zone lymphoma (SMZL) is a low-grade lymphoma showing a rather nonspecific immunophenotype. Gene expression profiling studies suggested that TCL1A could be a marker of SMZL, but reported data are conflicting. We evaluated TCL1A expression in a series of spleen and bone marrow samples involved by SMZL and correlated the findings with other immunophenotypical, morphological, and clinical data. In addition, we evaluated the expression of TCL1A in a series of spleens and lymph nodes involved by lymphomas that might mimic SMZL (13 nodal marginal zone lymphomas (NMZL), 39 follicular lymphomas (FL), 30 B-cell chronic lymphocytic leukemias (B-CLL), 31 mantle cell lymphomas (MCL), 1 lymphoplasmacytic lymphoma) and 15 bone marrow specimens involving hairy cell leukemia (HCL). TCL1A staining was negative in 24/31 cases of SMZL (77 %); 27/31 MCL and all B-CLL were positive for TCL1A; 32/34 cases of nodal FL (96 %) and all five splenic FL were positive for TCL1A, although at a lower intensity. Eight of 13 NMZL were positive for TCL1A, often showing a heterogeneous staining pattern. All HCL samples were strongly positive for TCL1A. No correlation was found between the pattern of splenic infiltration, TCL1A expression, and the clinical course. TCL1A-positive SMZL showed a higher rate of DBA44 staining compared to the negative ones, and this difference was statistically significant (Fisher test, single-tailed, p = 0.0397). Our data support the use of TCL1A in the panel of diagnostic markers used in the differential diagnosis of splenic low-grade B-cell lymphoma; a possible prognostic value, however, needs a larger series to be established.
Department of Pathology and Diagnostics, Section of Anatomic Pathology, University of Verona, P.le Scuro 10, 37134 Verona, Italy.
Enrico
E
Munari
Marianna
M
Rinaldi
Achille
A
Ambrosetti
Massimiliano
M
Bonifacio
Angela
A
Bonalumi
Marco
M
Chilosi
Alberto
A
Zamò
D014408:Biomarkers, Tumor / Q000378:metabolism*; D006801:Humans; D018442:Lymphoma, B-Cell, Marginal Zone / Q000175:diagnosis* / Q000473:pathology; D008228:Lymphoma, Non-Hodgkin / Q000175:diagnosis / Q000473:pathology; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D013160:Splenic Neoplasms / Q000175:diagnosis* / Q000473:pathology
D014408:Biomarkers, Tumor; D011518:Proto-Oncogene Proteins; C090851:TCL1A protein, human