title: Burden of cytogenetically abnormal plasma cells in light chain amyloidosis and their prognostic relevance.
abstract: We performed cytoplasmic fluorescence in situ hybridization assays of light chain amyloidosis (AL). In total, 234 patients were enrolled: 28 patients with AL, 24 with monoclonal gammopathy of undetermined significance (MGUS), and 182 with multiple myeloma (MM). Chromosomal abnormalities were detected in 13 of 22 (59%) AL patients without MM. All 13 patients demonstrated IGH rearrangement, and t(11;14)/IGH-CCND1 was most frequent (32%). Chromosome gain was not observed in AL patients without MM. These findings were dissimilar to findings in MGUS patients, in whom trisomy 9 was the most frequent abnormality. Of 6 AL patients with MM, 5 (83%) patients had cytogenetic abnormalities: 1q gain (4/6, 67%), gains of chromosome 9 (3/6, 50%), IGH rearrangement and RB1 (13q) deletions (2/6 each, 33%). The percentage of clonal plasma cells among total plasma cells was variable (median, 75%; range, 16-100%) for AL patients without MM, which was lower than the results for MM patients (median 100%). The overall survival of AL patients without MM was not significantly different according to the presence of cytogenetic abnormalities (P=0.510). In summary, among Korean AL patients, IGH rearrangement was the most frequent cytogenetic abnormality and cytogenetic aberration patterns differ compared with MGUS and MM patients.
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, South Korea; Department of Laboratory Medicine, Chungnam National University College of Medicine, Daejeon, South Korea.
authors.forename: Seon Young
authors.initials: SY
authors.lastname: Kim
authors.affiliation: Cancer Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Kyongok
authors.initials: K
authors.lastname: Im
authors.affiliation: Cancer Research Institute, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Si Nae
authors.initials: SN
authors.lastname: Park
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Jung-Ah
authors.initials: JA
authors.lastname: Kim
authors.affiliation: Cancer Research Institute, Seoul National University College of Medicine, Seoul, South Korea; Department of Internal Medicine, Seoul National University College of Medicine, Seoul, South Korea.
authors.forename: Sung-Soo
authors.initials: SS
authors.lastname: Yoon
authors.affiliation: Department of Laboratory Medicine, Seoul National University College of Medicine, Seoul, South Korea; Cancer Research Institute, Seoul National University College of Medicine, Seoul, South Korea. Electronic address: soonlee@snu.ac.kr.
authors.forename: Dong Soon
authors.initials: DS
authors.lastname: Lee
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000686:Amyloidosis / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D002869:Chromosome Aberrations; D002882:Chromosomes, Human, Pair 13 / Q000235:genetics; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007147:Immunoglobulin Light Chains / Q000235:genetics*; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D008875:Middle Aged; D008998:Monoclonal Gammopathy of Undetermined Significance / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D009101:Multiple Myeloma / Q000235:genetics / Q000401:mortality / Q000473:pathology*; D009367:Neoplasm Staging; D010950:Plasma Cells / Q000473:pathology*; D011379:Prognosis; D015996:Survival Rate
chemical_list: D007147:Immunoglobulin Light Chains
keywords: AL amyloidosis; Cytogenetics; Monoclonal gammopathy of undermined significance; Multiple myeloma