Fluorescence In Situ Hybridization Studies in 22 Cases of Plasma Cell Leukemia.

Background Plasma cell leukemia (PCL) is a rare malignant plasma cell disorder that usually carries an aggressive course with a rapidly fatal outcome. Cytogenetic studies performed on plasma cell disorder are scarce and difficult because of the low proliferation rate of plasma cells. Fluorescence in situ hybridization (FISH) analysis is an attractive alternative for evaluation of numerical and structural chromosomal changes in PCL. Methods Interphase FISH (I-FISH) and two different specific probes for the regions containing 13q14.3 (D13S319) or 14q32 (IGHC/IGHV) were used to detect 13q14 deletion [del(13q14)] or IgH rearrangement in 22 PCL patients. For patients with IgH rearrangement, probes for IgH(JH) and 11q13 (CCND1) or 4p16 (FGFR3) were used to detect t(11;14)(q13;q32) or t(4;14)(p16;q32). Results Molecular cytogenetic aberrations were found in 19 of 22 (86.4%) PCL patients. Del(13q14) was detected in 13 cases (59.1%), and IgH rearrangement in 17 (77.3%) patients including 7 with t(11;14) and 3 with t(4;14). 14q32 rearrangement and 13q14 deletion were found concurrently in 11 cases (50%). Conclusions Chromosomal abnormalities are frequent in PCL. The most frequent aberrations among the cases was the 14q32 rearrangement and 13q14 deletion. I-FISH technique is useful to detect molecular cytogenetic aberrations and should be used in the routine evaluation of PCL.