COMBINATION OF T(4;14), DEL(17P13), DEL(1P32) AND 1Q21 GAIN FISH PROBES IDENTIFIES CLONAL HETEROGENEITY AND ENHANCES DETECTION OF ADVERSE CYTOGENETIC PROFILES IN 233 NEWLY DIAGNOSED MULTIPLE MYELOMA
(Abstract release date: 05/19/16)
EHA Library. Smol T. 06/09/16; 132794; E1245
Dr. Thomas Smol
Contributions
Contributions
Abstract
Abstract: E1245
Type: Eposter Presentation
Background
Cytogenetic analyses play a leading part in the risk stratification of MM due to the prognostic and therapeutic impacts of cytogenetic abnormalities. However, with a metaphase cytogenetic approach only 35% of patients present abnormal karyotypes, often associated with an advanced stage of the disease. Practice guidelines now recommend interphase fluorescence in-situ hybridization (FISH) on isolated CD138-expressing plasma cells (PC) as the initial cytogenetic analysis for MM. The most pertinent markers target the deletion of 17p13 (TP53 deletion) and the t(4;14)(p16;q32) FGFR3-IGH translocation, and partial aneuploidies of chromosome 1 (1q21 gain and 1p32 deletion) are retained as more relevant additional markers.
Aims
Our aim was to fix the FISH combination of del(17p13), t(4;14), 1q21 gain and del(1p32) in a prospective study of 233 newly diagnosed MM with an analysis of the association between abnormalities and the number of clones.
Methods
Between January 2013 and August 2015, 233 BM samples were collected from 233 patients during diagnostic at the Cytogenetic Laboratories in Valenciennes General Hospital, and Versailles General Hospital. The institutional ethics committee approved the study. PC were enriched from BM mononuclear cells, using a magnetic cell sorting CD138 MicroBeads kit (Miltenyi Biotec; BergischGlabach, Germany). The FISH panel included TP53/CEP17 probe (Amplitech, Compiègne, France), 1p32/CDKN2C-FAF1 – 1q21/CKS1B probe (Amplitech), t(4;14)(p16;q32) probe (MetaSystems, Altlussheim, Germany), and IGH break-apart probe (MetaSystems). Technical thresholds were determined for each probe using isolated CD138-expressing PC from patients without MM, on the basis of the same method as patients with MM. Thresholds were assessed after counting 200 cells for each negative sample, and established by “mean + 3 DS” calculation.
Results
Cytogenetic abnormalities were identified in 79.0% of cases, with one or more adverse abnormalities in 51.9%. We observed a del(17p13) in 15.0%, a t(4;14) translocation in 11.5%, a 1q21 gain in 37.8%, and a del(1p32) in 8.7% of patients with statistically significant associations between 1q21 gain and t(4;14) (p = 0.001), and del(1p32) and del(17p13) (p = 0.01). Adding 1p32/1q21 FISH probe has enabled us to identify one or more adverse abnormalities in 39.0% of patients with absence of TP53 deletion or t(4;14). Clonal heterogeneity was observed in 51.1% of cases. Adverse abnormalities were significantly more frequent when the number of clones was greater than or equal to 2, with a frequency of 85.1% against 45.6% when 1 single clone was identified (p < 0.0001). We observed a greater number of MM with 1q21 gain when clonal heterogeneity was present (≥ 2 clones): 81.6% versus 18.4% when 1 single clone was identified (p < 0.0001). In the case of marked clonal heterogeneity (≥ 3 clones), a higher involvement of del(1p32) was found with a frequency of 28.0% against 5.8% when only 2 related clones were present (p = 0.002). In the subgroup t(4;14)+/1q21+ with 2 or more identified clones (n = 14), 1q21 gain was found to be significantly more often present in the minor clone compared to the clone with t(4;14) (10/14) (p = 0.01).
Conclusion
We were able to identify adverse abnormalities or derivative anomalies, and related clones or clonal evolution by FISH analysis. We confirm the presence of clonal heterogeneity and accumulation of adverse abnormalities in the first diagnostic analysis. The prognostic impact of these parameters should be evaluated, and could be included in cytogenetic classifications.
Session topic: E-poster
Keyword(s): Chromosomal abnormality, Clonality, FISH, Multiple myeloma
Type: Eposter Presentation
Background
Cytogenetic analyses play a leading part in the risk stratification of MM due to the prognostic and therapeutic impacts of cytogenetic abnormalities. However, with a metaphase cytogenetic approach only 35% of patients present abnormal karyotypes, often associated with an advanced stage of the disease. Practice guidelines now recommend interphase fluorescence in-situ hybridization (FISH) on isolated CD138-expressing plasma cells (PC) as the initial cytogenetic analysis for MM. The most pertinent markers target the deletion of 17p13 (TP53 deletion) and the t(4;14)(p16;q32) FGFR3-IGH translocation, and partial aneuploidies of chromosome 1 (1q21 gain and 1p32 deletion) are retained as more relevant additional markers.
Aims
Our aim was to fix the FISH combination of del(17p13), t(4;14), 1q21 gain and del(1p32) in a prospective study of 233 newly diagnosed MM with an analysis of the association between abnormalities and the number of clones.
Methods
Between January 2013 and August 2015, 233 BM samples were collected from 233 patients during diagnostic at the Cytogenetic Laboratories in Valenciennes General Hospital, and Versailles General Hospital. The institutional ethics committee approved the study. PC were enriched from BM mononuclear cells, using a magnetic cell sorting CD138 MicroBeads kit (Miltenyi Biotec; BergischGlabach, Germany). The FISH panel included TP53/CEP17 probe (Amplitech, Compiègne, France), 1p32/CDKN2C-FAF1 – 1q21/CKS1B probe (Amplitech), t(4;14)(p16;q32) probe (MetaSystems, Altlussheim, Germany), and IGH break-apart probe (MetaSystems). Technical thresholds were determined for each probe using isolated CD138-expressing PC from patients without MM, on the basis of the same method as patients with MM. Thresholds were assessed after counting 200 cells for each negative sample, and established by “mean + 3 DS” calculation.
Results
Cytogenetic abnormalities were identified in 79.0% of cases, with one or more adverse abnormalities in 51.9%. We observed a del(17p13) in 15.0%, a t(4;14) translocation in 11.5%, a 1q21 gain in 37.8%, and a del(1p32) in 8.7% of patients with statistically significant associations between 1q21 gain and t(4;14) (p = 0.001), and del(1p32) and del(17p13) (p = 0.01). Adding 1p32/1q21 FISH probe has enabled us to identify one or more adverse abnormalities in 39.0% of patients with absence of TP53 deletion or t(4;14). Clonal heterogeneity was observed in 51.1% of cases. Adverse abnormalities were significantly more frequent when the number of clones was greater than or equal to 2, with a frequency of 85.1% against 45.6% when 1 single clone was identified (p < 0.0001). We observed a greater number of MM with 1q21 gain when clonal heterogeneity was present (≥ 2 clones): 81.6% versus 18.4% when 1 single clone was identified (p < 0.0001). In the case of marked clonal heterogeneity (≥ 3 clones), a higher involvement of del(1p32) was found with a frequency of 28.0% against 5.8% when only 2 related clones were present (p = 0.002). In the subgroup t(4;14)+/1q21+ with 2 or more identified clones (n = 14), 1q21 gain was found to be significantly more often present in the minor clone compared to the clone with t(4;14) (10/14) (p = 0.01).
Conclusion
We were able to identify adverse abnormalities or derivative anomalies, and related clones or clonal evolution by FISH analysis. We confirm the presence of clonal heterogeneity and accumulation of adverse abnormalities in the first diagnostic analysis. The prognostic impact of these parameters should be evaluated, and could be included in cytogenetic classifications.
Session topic: E-poster
Keyword(s): Chromosomal abnormality, Clonality, FISH, Multiple myeloma
Abstract: E1245
Type: Eposter Presentation
Background
Cytogenetic analyses play a leading part in the risk stratification of MM due to the prognostic and therapeutic impacts of cytogenetic abnormalities. However, with a metaphase cytogenetic approach only 35% of patients present abnormal karyotypes, often associated with an advanced stage of the disease. Practice guidelines now recommend interphase fluorescence in-situ hybridization (FISH) on isolated CD138-expressing plasma cells (PC) as the initial cytogenetic analysis for MM. The most pertinent markers target the deletion of 17p13 (TP53 deletion) and the t(4;14)(p16;q32) FGFR3-IGH translocation, and partial aneuploidies of chromosome 1 (1q21 gain and 1p32 deletion) are retained as more relevant additional markers.
Aims
Our aim was to fix the FISH combination of del(17p13), t(4;14), 1q21 gain and del(1p32) in a prospective study of 233 newly diagnosed MM with an analysis of the association between abnormalities and the number of clones.
Methods
Between January 2013 and August 2015, 233 BM samples were collected from 233 patients during diagnostic at the Cytogenetic Laboratories in Valenciennes General Hospital, and Versailles General Hospital. The institutional ethics committee approved the study. PC were enriched from BM mononuclear cells, using a magnetic cell sorting CD138 MicroBeads kit (Miltenyi Biotec; BergischGlabach, Germany). The FISH panel included TP53/CEP17 probe (Amplitech, Compiègne, France), 1p32/CDKN2C-FAF1 – 1q21/CKS1B probe (Amplitech), t(4;14)(p16;q32) probe (MetaSystems, Altlussheim, Germany), and IGH break-apart probe (MetaSystems). Technical thresholds were determined for each probe using isolated CD138-expressing PC from patients without MM, on the basis of the same method as patients with MM. Thresholds were assessed after counting 200 cells for each negative sample, and established by “mean + 3 DS” calculation.
Results
Cytogenetic abnormalities were identified in 79.0% of cases, with one or more adverse abnormalities in 51.9%. We observed a del(17p13) in 15.0%, a t(4;14) translocation in 11.5%, a 1q21 gain in 37.8%, and a del(1p32) in 8.7% of patients with statistically significant associations between 1q21 gain and t(4;14) (p = 0.001), and del(1p32) and del(17p13) (p = 0.01). Adding 1p32/1q21 FISH probe has enabled us to identify one or more adverse abnormalities in 39.0% of patients with absence of TP53 deletion or t(4;14). Clonal heterogeneity was observed in 51.1% of cases. Adverse abnormalities were significantly more frequent when the number of clones was greater than or equal to 2, with a frequency of 85.1% against 45.6% when 1 single clone was identified (p < 0.0001). We observed a greater number of MM with 1q21 gain when clonal heterogeneity was present (≥ 2 clones): 81.6% versus 18.4% when 1 single clone was identified (p < 0.0001). In the case of marked clonal heterogeneity (≥ 3 clones), a higher involvement of del(1p32) was found with a frequency of 28.0% against 5.8% when only 2 related clones were present (p = 0.002). In the subgroup t(4;14)+/1q21+ with 2 or more identified clones (n = 14), 1q21 gain was found to be significantly more often present in the minor clone compared to the clone with t(4;14) (10/14) (p = 0.01).
Conclusion
We were able to identify adverse abnormalities or derivative anomalies, and related clones or clonal evolution by FISH analysis. We confirm the presence of clonal heterogeneity and accumulation of adverse abnormalities in the first diagnostic analysis. The prognostic impact of these parameters should be evaluated, and could be included in cytogenetic classifications.
Session topic: E-poster
Keyword(s): Chromosomal abnormality, Clonality, FISH, Multiple myeloma
Type: Eposter Presentation
Background
Cytogenetic analyses play a leading part in the risk stratification of MM due to the prognostic and therapeutic impacts of cytogenetic abnormalities. However, with a metaphase cytogenetic approach only 35% of patients present abnormal karyotypes, often associated with an advanced stage of the disease. Practice guidelines now recommend interphase fluorescence in-situ hybridization (FISH) on isolated CD138-expressing plasma cells (PC) as the initial cytogenetic analysis for MM. The most pertinent markers target the deletion of 17p13 (TP53 deletion) and the t(4;14)(p16;q32) FGFR3-IGH translocation, and partial aneuploidies of chromosome 1 (1q21 gain and 1p32 deletion) are retained as more relevant additional markers.
Aims
Our aim was to fix the FISH combination of del(17p13), t(4;14), 1q21 gain and del(1p32) in a prospective study of 233 newly diagnosed MM with an analysis of the association between abnormalities and the number of clones.
Methods
Between January 2013 and August 2015, 233 BM samples were collected from 233 patients during diagnostic at the Cytogenetic Laboratories in Valenciennes General Hospital, and Versailles General Hospital. The institutional ethics committee approved the study. PC were enriched from BM mononuclear cells, using a magnetic cell sorting CD138 MicroBeads kit (Miltenyi Biotec; BergischGlabach, Germany). The FISH panel included TP53/CEP17 probe (Amplitech, Compiègne, France), 1p32/CDKN2C-FAF1 – 1q21/CKS1B probe (Amplitech), t(4;14)(p16;q32) probe (MetaSystems, Altlussheim, Germany), and IGH break-apart probe (MetaSystems). Technical thresholds were determined for each probe using isolated CD138-expressing PC from patients without MM, on the basis of the same method as patients with MM. Thresholds were assessed after counting 200 cells for each negative sample, and established by “mean + 3 DS” calculation.
Results
Cytogenetic abnormalities were identified in 79.0% of cases, with one or more adverse abnormalities in 51.9%. We observed a del(17p13) in 15.0%, a t(4;14) translocation in 11.5%, a 1q21 gain in 37.8%, and a del(1p32) in 8.7% of patients with statistically significant associations between 1q21 gain and t(4;14) (p = 0.001), and del(1p32) and del(17p13) (p = 0.01). Adding 1p32/1q21 FISH probe has enabled us to identify one or more adverse abnormalities in 39.0% of patients with absence of TP53 deletion or t(4;14). Clonal heterogeneity was observed in 51.1% of cases. Adverse abnormalities were significantly more frequent when the number of clones was greater than or equal to 2, with a frequency of 85.1% against 45.6% when 1 single clone was identified (p < 0.0001). We observed a greater number of MM with 1q21 gain when clonal heterogeneity was present (≥ 2 clones): 81.6% versus 18.4% when 1 single clone was identified (p < 0.0001). In the case of marked clonal heterogeneity (≥ 3 clones), a higher involvement of del(1p32) was found with a frequency of 28.0% against 5.8% when only 2 related clones were present (p = 0.002). In the subgroup t(4;14)+/1q21+ with 2 or more identified clones (n = 14), 1q21 gain was found to be significantly more often present in the minor clone compared to the clone with t(4;14) (10/14) (p = 0.01).
Conclusion
We were able to identify adverse abnormalities or derivative anomalies, and related clones or clonal evolution by FISH analysis. We confirm the presence of clonal heterogeneity and accumulation of adverse abnormalities in the first diagnostic analysis. The prognostic impact of these parameters should be evaluated, and could be included in cytogenetic classifications.
Session topic: E-poster
Keyword(s): Chromosomal abnormality, Clonality, FISH, Multiple myeloma
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