High-Risk Plasma Cell Myeloma Cytogenetic Markers Are More Prevalent in African-Americans
L Taddesse-Heath, J Scheerle, JC Kelly, A Meloni-Ehrig. Howard University Hospital, Washington, DC; Quest Diagnostics Nichols Institute, Chantilly, VA
Background: Plasma cell myeloma (PCM) is more common in African-Americans compared to Caucasians with a two-fold increased incidence and a higher mortality rate. The reasons for these differences are not well understood. The genetic changes of PCM and their impact on disease outcome have been well characterized, however, the data were largely derived from Caucasians and there are no studies that describe the incidence of myeloma-associated genetic changes specifically in African-Americans.
Design: We retrospectively reviewed demographic data, bone marrow biopsies and cytogenetic studies of 36 consecutive African-American patients with PCM from 2003-2008.
Results: The male to female ratio was 1.6:1. The age range was 28-91 years with a median of 63. Karyotypic abnormalities were present in 41% (15/36) of the patients. Of these, 93% (14/15) showed a complex karyotype with 40% (6/15) having a pseudo-diploid/hypodiploid karyotype (≤46 chromosomes) whereas 60% (9/15) showed a hyperdiploid karyotype. Among the 15 patients with abnormal karyotype, 80% (12) showed -13/13q- and or -17/17p-. Specifically, 13/13q deletions were present in 67% (10/15), whereas, 17/17p deletions were present in 53% (8/15) of the patients at initial diagnosis. Rearrangements (deletions and translocations) involving the immunoglobulin heavy chain 14q32 were present in 33% (5/15), one of which was a translocation (11;14)(q13;q32).
Conclusions: The karyotypic aberrations in African-American patients with PCM appear to be more complex, with a high incidence of abnormalities associated with poor prognosis and high-risk categories. Particularly, deletions of chromosome 17p were observed at initial diagnosis at a significantly higher rate in African-Americans compared with those reported for the general population (53% vs.10%). These findings may shed light on the differential risk and poorer outcome of PCM in African-Americans.
Tuesday, March 23, 2010 9:30 AM
Poster Session III # 206, Tuesday Morning