title: Amplification of 1q21 and other abnormalities in multiple myeloma patients from a tertiary hospital in singapore.
abstract: Much effort has been made to stratify multiple myeloma patients for targeted therapy. However, responses have been varied and improved patient stratifications are needed. Forty-five diagnostic samples from multiple myeloma patients (median age 65 years) were stratified cytogenetically as 15 having non-hyperdiploidy, 20 having hyperdiploidy and 10 having a normal karyotype. Fluorescence in situ hybridization (FISH) assays with FGFR3/IGH, CCND1/IGH, IGH/MAF, RB1 and TP53 probes on bone marrow samples showed that IGH rearrangements were the most common abnormality in the non-hyperdiploid group but these were also found among hyperdiploid patients and patients with normal cytogenetics. Of these, FGFR3/IGH rearrangements were most frequent. Deletion of RB1/monosomy 13 was the most common genetic abnormality across the three groups and was significantly higher among non-hyperdiploid compared to hyperdiploid patients. On the other hand, the study recorded a low incidence of TP53 deletion/monosomy 17. The FGFR3/IGH fusion was frequently seen with RB1 deletion/monosomy 13. FISH with 1p36/1q21 and 6q21/15q22 probes showed that amplification of 15q22 was seen in all of the hyperdiploid patients while amplification of 1q21, Amp(1q21), characterized non-hyperdiploid patients. In contrast, deletions of 1p36 and 6q21 were very rare events. Amp(1q21), FGFR3/IGH fusion, RB1 deletion/monosomy 13, and even TP53 deletion/monosomy 17 were seen in some hyperdiploid patients, suggesting that they have a less than favorable prognosis and require closer monitoring.
authors.affiliation: Cytogenetics Laboratory, Department of Pathology, Singapore General Hospital, The Academia-Diagnostics Tower, L9, 20 College Road, Singapore, 169856 Singapore.
authors.forename: Alvin S T
authors.initials: AS
authors.lastname: Lim
authors.affiliation: Department of Haematology, Singapore General Hospital, Singapore, Singapore.
authors.forename: Sathish
authors.initials: S
authors.lastname: Krishnan
authors.affiliation: Cytogenetics Laboratory, Department of Pathology, Singapore General Hospital, The Academia-Diagnostics Tower, L9, 20 College Road, Singapore, 169856 Singapore.
authors.forename: Tse Hui
authors.initials: TH
authors.lastname: Lim
authors.affiliation: Cytogenetics Laboratory, Department of Pathology, Singapore General Hospital, The Academia-Diagnostics Tower, L9, 20 College Road, Singapore, 169856 Singapore.
authors.forename: Karen
authors.initials: K
authors.lastname: See
authors.affiliation: Cytogenetics Laboratory, Department of Pathology, Singapore General Hospital, The Academia-Diagnostics Tower, L9, 20 College Road, Singapore, 169856 Singapore.
authors.forename: Yit Jun
authors.initials: YJ
authors.lastname: Ng
authors.affiliation: School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
authors.forename: Yu Min
authors.initials: YM
authors.lastname: Tan
authors.affiliation: School of Biological Sciences, Nanyang Technological University, Singapore, Singapore.
authors.forename: Natasha
authors.initials: N
authors.lastname: Choo
authors.affiliation: Cytogenetics Laboratory, Department of Pathology, Singapore General Hospital, The Academia-Diagnostics Tower, L9, 20 College Road, Singapore, 169856 Singapore.
authors.forename: Lai Ching
authors.initials: LC
authors.lastname: Lau
authors.affiliation: Cytogenetics Laboratory, Department of Pathology, Singapore General Hospital, The Academia-Diagnostics Tower, L9, 20 College Road, Singapore, 169856 Singapore ; Department of Haematology, Singapore General Hospital, Singapore, Singapore.
authors.forename: Sim Leng
authors.initials: SL
authors.lastname: Tien
authors.affiliation: Faculty of Medicine, Nursing and Health Sciences, Monash University, Melbourne, VIC Australia.
authors.forename: Jun
authors.initials: J
authors.lastname: Ma
authors.affiliation: Department of Haematology, Singapore General Hospital, Singapore, Singapore.
authors.forename: Daryl
authors.initials: D
authors.lastname: Tan
keywords: Amp(1q21); FISH panel; Hyperdiploidy; Non-hyperdiploidy