LightCycler-based quantitative real-time PCR monitoring of patients with follicular lymphoma receiving rituximab in combination with conventional or high-dose cytotoxic chemotherapy.
OBJECTIVE
Quantitative real-time polymerase chain reaction (qPCR) is a suitable method to measure residual disease in hematological malignancies. Our objective was to assess a LightCycler-based qPCR for t(14;18)(q32;q21)(IgH/bcl-2)-positive cells quantification in the context of clinical and morphopathological characteristics of patients with follicular lymphoma treated with rituximab (R) in combination with conventional or high-dose chemotherapy.


METHODS
A total of 270 bone marrow (BM) and peripheral blood (PB) samples collected from 52 patients with follicular lymphoma at diagnosis or at relapse before or sequentially during therapy were examined by qPCR and nested-PCR.


RESULTS
A greater amount of t(14;18)-positive cells was observed in BM in comparison with PB in 76% of paired samples. The presence and number of t(14;18)-positive cells in BM and PB correlated with lymphoma activity. Significantly higher numbers of lymphoma cells were found in patients under non-remission compared with patients in clinical remission. During non-remission, 10-fold higher numbers were measured at relapse than at diagnosis. During remission, significantly higher levels were found in partial compared with complete remission. During first-line therapy, R/cyclophosphamide/adriamycin/vincristine/prednisone (CHOP) had higher in vivo purging ability than R/fludarabine/mitoxantrone (FM). After R/high-dose cytosine-arabinoside and mitoxantrone (HAM) or R/carmustine/etoposide/cytarabine/melphalan (BEAM), the level of t(14;18)-positive cells dropped below the detection limit in 80% of patients.


CONCLUSIONS
LightCycler qPCR is a reliable method for quantitative molecular monitoring of t(14;18)-positive cells in BM and PB of patients with follicular lymphoma. It reflects the clinical characteristics of patients and allows assessment of response to different treatment regimens on a molecular level.
Martin
Simona
S
Department of Hematology, Oncology and Clinical Immunology, University of Duesseldorf, Germany. simona.martin@itu.fzk.de
Fischer
Christian
C
Free
Maren
M
Kurreck
Baerbel
B
Stockinger
Hubertus
H
Fenk
Roland
R
Arnold
Carolin
C
Kliszewski
Slawomir
S
Meckenstock
Gerald
G
Haas
Rainer
R
Kronenwett
Ralf
R
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D058846:Antibodies, Monoclonal, Murine-Derived; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D001773:Blood Cells / Q000378:metabolism; D001854:Bone Marrow Cells / Q000378:metabolism; D002883:Chromosomes, Human, Pair 14 / Q000235:genetics; D002887:Chromosomes, Human, Pair 18 / Q000235:genetics; D003131:Combined Modality Therapy; D005260:Female; D006801:Humans; D008224:Lymphoma, Follicular / Q000188:drug therapy / Q000235:genetics* / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction / Q000379:methods* / Q000706:statistics & numerical data; D012008:Recurrence; D000069283:Rituximab; D012680:Sensitivity and Specificity; D014178:Translocation, Genetic
D000911:Antibodies, Monoclonal; D058846:Antibodies, Monoclonal, Murine-Derived; D000069283:Rituximab