A Variant Burkitt-Type Translocation (8;22)(q24;q11) in Multiple Myeloma: Report of a New Case and Review of the Literature

We report here a new case of multiple myeloma (IgG, κ, stage IIIA) with a variant Burkitt-type translocation (8;22)(q24;q11). Bone marrow plasma cells were morphologically immature with fine nuclear chromatin and nucleoli. Chromosome analysis showed complex aberrations; that is, 53,XX,der(1)add(1)(p11)dup(1)(q12q32),+3,+5,t(8;22)(q24;q11),+9,add(10)(p13),+11,+15,add(19)(q13),+21. Fluorescence in situ hybridization analysis with the yeast artificial chromosome (YAC) clone I2 containing the C-MYC gene at 8q24 and the chromosome-22-specific DNA library pBS22 revealed that I2 was located on the der(8)t(8;22). A fusion signal derived from I2 and the YAC clone B99E1 containing the BCR gene at 22q11 was also observed on the der(8)t(8;22). Our results indicate that the breakpoint at 8q24 in this patient was located far downstream of the C-MYC gene. This breakpoint site is similar to Burkitt lymphoma with t(8;22)(q24;q11). A review of eight cases in the literature and the present case of multiple myeloma with t(8;22)(q24;q11) showed that most of them were of advanced stage and had an immature phenotype. It is suggested that the C-MYC gene may be activated by t(8;22)(q24;q11) and implicated in disease progression in multiple myeloma.