Contributions
Abstract: PB2336
Type: Publication Only
Background
Splenic Lymphomas are rare diseases often misdiagnosed as hairy cell leukemia (HCL), splenic diffuse red pulp lymphoma (SDRPL) and splenic marginal zone lymphoma (SMZL). Criteria for differential diagnosis of these diseases are still controversial and require further elaboration.
Aims
The aim of our study is to determine the immunoglobulin variable heavy chain (IGHV) gene usage and somatic mutation patterns in a series of SDRPL and SMZL patients.
Methods
We studied 10 patients with SDRPL and 24 patients with SMZL (2014-2017 years). Diagnosis was based on standard WHO criteria. In all patients, the diagnosis was based on peripheral blood and BM findings. The baseline clinical and laboratory features as well as follow-up and outcome were recorded for every patient. IGHV mutational status was determined by Sanger sequencing. Cases with 98% or higher IGHV gene homology to germinal sequences were considered unmutated.
Results
Two cases (20%) of SDRPL were shown to bear unmutated IGHV genes whereas 8 (80%) - mutated. In 5 cases (50%) genes of VH3 family were found; in other 5 (50%) - genes of VH4 family. No preference for certain VH genes (from families 3 or 4) were observed. VH1 gene usage was not detected. In 9 cases (37.5%) of SMZL unmutated IGHV genes were detected and in 15 (62,5%) - mutated. VH1 gene family usage was found in 14 (58%) SMZL patients; most of them (12 patients, 86%) carrying IGHV1-2 gene (unmutated in 6 cases and mutated also in 6 cases). VH3 gene family usage was found in 7 SMZL patients (3 cases represent distinct IGHV3-7 gene) and 3 cases had different genes from VH4 family.
Conclusion
Despite the limited number of cases analyzed it should be concluded that IGHV mutational status may not be used to distinguish between SDRPL and SMZL since both diseases are shown to be associated with mutated as well as unmutated IGHV genes. However IGHV1-2 gene usage may strongly indicate SMZL. These findings have to be confirmed on extended sets of disease cases.
Session topic: 19. Non-Hodgkin lymphoma Biology & Translational Research
Keyword(s): Hairy cell leukemia, IgH rearrangment, Splenic marginal zone lymphoma
Abstract: PB2336
Type: Publication Only
Background
Splenic Lymphomas are rare diseases often misdiagnosed as hairy cell leukemia (HCL), splenic diffuse red pulp lymphoma (SDRPL) and splenic marginal zone lymphoma (SMZL). Criteria for differential diagnosis of these diseases are still controversial and require further elaboration.
Aims
The aim of our study is to determine the immunoglobulin variable heavy chain (IGHV) gene usage and somatic mutation patterns in a series of SDRPL and SMZL patients.
Methods
We studied 10 patients with SDRPL and 24 patients with SMZL (2014-2017 years). Diagnosis was based on standard WHO criteria. In all patients, the diagnosis was based on peripheral blood and BM findings. The baseline clinical and laboratory features as well as follow-up and outcome were recorded for every patient. IGHV mutational status was determined by Sanger sequencing. Cases with 98% or higher IGHV gene homology to germinal sequences were considered unmutated.
Results
Two cases (20%) of SDRPL were shown to bear unmutated IGHV genes whereas 8 (80%) - mutated. In 5 cases (50%) genes of VH3 family were found; in other 5 (50%) - genes of VH4 family. No preference for certain VH genes (from families 3 or 4) were observed. VH1 gene usage was not detected. In 9 cases (37.5%) of SMZL unmutated IGHV genes were detected and in 15 (62,5%) - mutated. VH1 gene family usage was found in 14 (58%) SMZL patients; most of them (12 patients, 86%) carrying IGHV1-2 gene (unmutated in 6 cases and mutated also in 6 cases). VH3 gene family usage was found in 7 SMZL patients (3 cases represent distinct IGHV3-7 gene) and 3 cases had different genes from VH4 family.
Conclusion
Despite the limited number of cases analyzed it should be concluded that IGHV mutational status may not be used to distinguish between SDRPL and SMZL since both diseases are shown to be associated with mutated as well as unmutated IGHV genes. However IGHV1-2 gene usage may strongly indicate SMZL. These findings have to be confirmed on extended sets of disease cases.
Session topic: 19. Non-Hodgkin lymphoma Biology & Translational Research
Keyword(s): Hairy cell leukemia, IgH rearrangment, Splenic marginal zone lymphoma