Biallelic IgH rearrangements in patients with indolent lymphoproliferative disorders: molecular and practical implications.
We report a group of patients (pts) with indolent lymphoproliferative disorder who had both alleles for the immunoglobulin heavy chain genes rearranged (biIgH). This group of 17 pts consisted of 9 small lymphocytic lymphomas (SLL) and 8 chronic lymphocytic leukemia (CLL). The polymerase chain reaction (PCR) amplification of clonal immunoglobulin heavy (IgH) rearrangement using the complementarity determining region III (CDRIII) constantly retrieved two distinct bands in all PCR informative samples of those pts. To rule out biclonality, we evaluated samples by fluorescein activated cell sorting (FACS) analysis and sequenced the PCR products. We were able to obtain both IgH sequences from 12 patients. FACS suggested biclonality in one case, which also correlated with sequencing results as both IgH rearrangements were in-frame. Recently, we reported a patient who sustained transformation into an aggressive disease after biIgH was detected in the setting of monoclonal disease (Cerny et al., 2003b, Haematologica 88(05):ECR15 B.). We decided to compare clinical characteristics and prognosis of 17 pts with biIgH and 37 pts with monoIgH rearrangements. Although we found some minor differences in disease characteristics between both groups, these did not translate into a significantly different overall survival. Our findings suggest that true biclonal cases of CLL are rare.
Cerny
Jan
J
1st Department of Internal Medicine, Charles University General Hospital, Prague, Czech Republic. jcern@hotmail.com
Slavickova
Alena
A
Krepelova
Anna
A
Trneny
Marek
M
Karban
Josef
J
Klener
Pavel
P
D000328:Adult; D000368:Aged; D000483:Alleles; D004273:DNA, Neoplasm / Q000032:analysis*; D005260:Female; D005434:Flow Cytometry; D015326:Gene Rearrangement, B-Lymphocyte, Heavy Chain; D006801:Humans; D007091:Image Processing, Computer-Assisted; D016130:Immunophenotyping; D015451:Leukemia, Lymphocytic, Chronic, B-Cell / Q000235:genetics*; D007945:Leukemia, Lymphoid / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011379:Prognosis
D004273:DNA, Neoplasm