Commercial LightCycler-based quantitative real-time PCR compared to nested PCR for monitoring of Bcl-2/IgH rearrangement in patients with follicular lymphoma.
Translocation of chromosomes 14 and 18 [t(14;18)] for detection of minimal residual disease in follicular lymphoma patients can be analyzed by nested polymerase chain reaction (PCR) or by quantitative PCR like LightCycler-based assays. We have compared both methods in blood and bone marrow samples of 28 patients enrolled in a clinical study on immunochemotherapy. In 42% of samples, the bcl2-IgH rearrangement was detectable by nested PCR, but not by LightCycler PCR. Nested PCR was able to reveal a significant drop in positive bone marrow or peripheral blood samples after therapy. In contrast, with LightCycler PCR, the detected drop in t(14;18)-positive cells did not reach statistical significance. The majority of patients showed positive results with nested PCR of peripheral blood or bone marrow without any associations to presence or absence of histological bone marrow (BM) infiltration by lymphoma cells. With LightCycler PCR, the numbers of positive cells were higher in samples from patients with BM infiltration of lymphoma cells (1.9 x 10(-2)) compared to samples from patients without involvement (4.08 x 10(-5)). A similar trend was seen in samples derived from the peripheral blood. Positivity for t(14;18) after therapy in two patients correlated with clinical relapse 6 months later. The data shown here demonstrate a lower sensitivity of LightCycler vs. nested PCR for detection of t(14;18). The usefulness of nested PCR for t(14;18) for risk stratification after primary therapy has to be validated in larger trials.
Kornacker
M
M
Department of Hematology, Oncology and Rheumatology, University of Heidelberg, Im Neuenheimer Feld 410, 69120 Heidelberg, Germany. martin.kornacker@arcormail.de
Kornacker
B
B
Schmitt
C
C
Leo
E
E
Ho
A D
AD
Hensel
M
M
D000328:Adult; D000368:Aged; D001853:Bone Marrow / Q000378:metabolism; D017322:Clinical Trials, Phase II as Topic; D005260:Female; D015321:Gene Rearrangement; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D008224:Lymphoma, Follicular / Q000235:genetics* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015337:Multicenter Studies as Topic; D018365:Neoplasm, Residual; D016133:Polymerase Chain Reaction / Q000295:instrumentation / Q000379:methods; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D016032:Randomized Controlled Trials as Topic; D012680:Sensitivity and Specificity
D007143:Immunoglobulin Heavy Chains; D019253:Proto-Oncogene Proteins c-bcl-2