Contributions
Abstract: PB1686
Type: Publication Only
Session title: Myeloma and other monoclonal gammopathies - Clinical
Background
Multiple myeloma (MM) is a clonal malignant hematological disease characterized by a broad range of genetic abnormalities that contribute to the disease course, treatment outcome and overall survival. Metaphase cytogenetics requires proliferating cells and is not sensitive for the detection of primary or secondary cytogenetic abnormalities. Nevertheless, any finding of a metaphase-detected abnormality is probably associated with more proliferative and aggressive form of MM.
Aims
The aim of the study is to define the role of conventional cytogenetics in the disease phenotype, time to next treatment (TNT) and overall survival (OS).
Methods
We analyzed 103 patients with newly diagnosed MM between February 2012 – December 2020. Mean age of the group is 62,3; male:female ratio - 1,06:1. According to ISS: 25,2% (n=26) are stage I; 18,4% (n=19) - stage II and 56,3% (n=58) - stage III. 36,5% are IgG kappa, 15,5% gG lambda, 10,7% IgA kappa, 6,8% IgA lambda, 22,3% FLC myeloma, 2,9% non secretory myeloma and 1,9% biclonal myeloma, 2,9% plasma cell leukemia. Regarding lines of therapy, 54,4% received 1, 23,3% - 2, 13,6% - 3, 3,9% - 4 lines of therapy and 4,9% did not receive any treatment. G-banding was performed on bone marrow samples. The cytogenetic risk was determined according to the Mayo Algorithmic Approach for Stratification of Myeloma and Risk-Adapted Therapy (mSMART) classification v.3.0. Patients with high risk are 8,7%, standard risk-82,5%. In 8,7% metaphases for cytogenetics are not obtained. Patients are distributed in 8 groups based on karyotype: normal karyotype-74,8%, hypodiploids-6,8%, hyperdiploids-2,9%, diploid-1,9%, high risk deletions-2,9%. One patient is with pseudodiploid karyotype and one is with complex karyotype. Statistical analysis is performed with SPSS v.19.
Results
By crosstab descriptive analysis approximately half of the patients with standard cytogenetic risk are stratified in ISS 3-54,1% (n=46). In the high risk group 81,8% are categorized in ISS 3. Regarding the karyotype classification, in ISS 1, 20 of the patients are with normal karyotype and only 2 have pathological karyotype: one is hypodiploid and one is with del(21)(q22). In the ISS 2, from 19 patients 17 are with normal karyotype and 1 is hyperdiploid. In ISS 3 the distribution is heterogeneous with normal karyotype in 40; hypodiploids in 6; hylerdiploid in 2, pseiudodiploid in 1, diploid in 2, high risk deletions in 2 and complex karyotype in one patient. The mean OS of the whole group is 39,7±4,2 months. We found significant difference in the mean OS based on the cytogenetic risk - 40,8±4,4 months in standard risk and 19,6±6,9 in high risk group (p<0,05). We found a significant difference in the time to third treatment (TTT) within the cytogenetic risk groups (p<0,001). The mean TTT in patients with standard risk is 2,1±5,2 months compared to 0 months in high risk group. We found a tendency showing that patients with standard risk have longer time to second treatment (TST) compared to those with high risk (12,9±18,8 months; 4,5±9 months; p=0,6). There is no difference between number of therapies, cytogenetic profile and myeloma type according to the karyotype.
Conclusion
The cytogenetic profile in MM is of utmost importance for risk stratification. Deviations from the normal karyotype detected by G-banding are found in approximately 20% of patients. Despite the importance of FISH-based risk stratification of MM, the role of conventional cytogenetics should not be underestimated, giving the opportunity of detecting a vast majority of cytogenetic abnormalities.
Keyword(s): Cytogenetics, Multiple myeloma
Abstract: PB1686
Type: Publication Only
Session title: Myeloma and other monoclonal gammopathies - Clinical
Background
Multiple myeloma (MM) is a clonal malignant hematological disease characterized by a broad range of genetic abnormalities that contribute to the disease course, treatment outcome and overall survival. Metaphase cytogenetics requires proliferating cells and is not sensitive for the detection of primary or secondary cytogenetic abnormalities. Nevertheless, any finding of a metaphase-detected abnormality is probably associated with more proliferative and aggressive form of MM.
Aims
The aim of the study is to define the role of conventional cytogenetics in the disease phenotype, time to next treatment (TNT) and overall survival (OS).
Methods
We analyzed 103 patients with newly diagnosed MM between February 2012 – December 2020. Mean age of the group is 62,3; male:female ratio - 1,06:1. According to ISS: 25,2% (n=26) are stage I; 18,4% (n=19) - stage II and 56,3% (n=58) - stage III. 36,5% are IgG kappa, 15,5% gG lambda, 10,7% IgA kappa, 6,8% IgA lambda, 22,3% FLC myeloma, 2,9% non secretory myeloma and 1,9% biclonal myeloma, 2,9% plasma cell leukemia. Regarding lines of therapy, 54,4% received 1, 23,3% - 2, 13,6% - 3, 3,9% - 4 lines of therapy and 4,9% did not receive any treatment. G-banding was performed on bone marrow samples. The cytogenetic risk was determined according to the Mayo Algorithmic Approach for Stratification of Myeloma and Risk-Adapted Therapy (mSMART) classification v.3.0. Patients with high risk are 8,7%, standard risk-82,5%. In 8,7% metaphases for cytogenetics are not obtained. Patients are distributed in 8 groups based on karyotype: normal karyotype-74,8%, hypodiploids-6,8%, hyperdiploids-2,9%, diploid-1,9%, high risk deletions-2,9%. One patient is with pseudodiploid karyotype and one is with complex karyotype. Statistical analysis is performed with SPSS v.19.
Results
By crosstab descriptive analysis approximately half of the patients with standard cytogenetic risk are stratified in ISS 3-54,1% (n=46). In the high risk group 81,8% are categorized in ISS 3. Regarding the karyotype classification, in ISS 1, 20 of the patients are with normal karyotype and only 2 have pathological karyotype: one is hypodiploid and one is with del(21)(q22). In the ISS 2, from 19 patients 17 are with normal karyotype and 1 is hyperdiploid. In ISS 3 the distribution is heterogeneous with normal karyotype in 40; hypodiploids in 6; hylerdiploid in 2, pseiudodiploid in 1, diploid in 2, high risk deletions in 2 and complex karyotype in one patient. The mean OS of the whole group is 39,7±4,2 months. We found significant difference in the mean OS based on the cytogenetic risk - 40,8±4,4 months in standard risk and 19,6±6,9 in high risk group (p<0,05). We found a significant difference in the time to third treatment (TTT) within the cytogenetic risk groups (p<0,001). The mean TTT in patients with standard risk is 2,1±5,2 months compared to 0 months in high risk group. We found a tendency showing that patients with standard risk have longer time to second treatment (TST) compared to those with high risk (12,9±18,8 months; 4,5±9 months; p=0,6). There is no difference between number of therapies, cytogenetic profile and myeloma type according to the karyotype.
Conclusion
The cytogenetic profile in MM is of utmost importance for risk stratification. Deviations from the normal karyotype detected by G-banding are found in approximately 20% of patients. Despite the importance of FISH-based risk stratification of MM, the role of conventional cytogenetics should not be underestimated, giving the opportunity of detecting a vast majority of cytogenetic abnormalities.
Keyword(s): Cytogenetics, Multiple myeloma