PCR-detectable nonneoplastic Bcl-2/IgH rearrangements are common in normal subjects and cancer patients at diagnosis but rare in subjects treated with chemotherapy.
OBJECTIVE
To assess whether nonneoplastic Bcl-2/IgH rearrangements act as a confounding factor in the setting of minimal residual disease analysis by evaluating their incidence in a panel of lymphoma-free subjects, including cancer-free donors and chemotherapy-naive and chemotherapy-treated cancer patients.


METHODS
A total of 501 nonlymphoma subjects have been assessed: 258 cancer-free patients and 243 patients with malignancies other than lymphoma, 112 of whom were chemotherapy-naive. Patients were primarily assessed by nested polymerase chain reaction (PCR), followed by real-time quantitative PCR if they scored positive. In addition, six initially PCR-positive cancer-free donors were prospectively reassessed by qualitative and quantitative PCR after 30 and 60 days.


RESULTS
The overall incidence of Bcl-2/IgH positivity was 9.6%, with a median number of 11 rearrangements per 1,000,000 diploid genomes (range, 0 to 2,845 rearrangements), as assessed by real-time PCR. The incidence was similar in healthy subjects and cancer patients at diagnosis (12% and 12.5%; P = not significant). In contrast, the incidence of this translocation was only 2.3% in chemotherapy-treated patients (P <.001). In addition, three initially PCR-positive cancer-free donors showed persistence of their rearrangements when assessed after 30 and 60 days.


CONCLUSIONS
The low incidence of nonneoplastic Bcl-2/IgH rearrangements following chemotherapy provides further evidence of the prognostic role of persistent PCR-positivity in the posttreatment molecular follow-up of follicular lymphoma patients.
Ladetto
Marco
M
Divisione di Ematologia, Dipartimento di Medicina ed Oncologia Sperimentale-Universita' di Torino, Italy. marco.ladetto@unito.it
Drandi
Daniela
D
Compagno
Mara
M
Astolfi
Monica
M
Volpato
Federica
F
Voena
Claudia
C
Novarino
Anna
A
Pollio
Berardino
B
Addeo
Alfredo
A
Ricca
Irene
I
Falco
Patrizia
P
Cavallo
Federica
F
Vallet
Sonia
S
Corradini
Paolo
P
Pileri
Alessandro
A
Tamponi
Giacomo
G
Palumbo
Antonio
A
Bertetto
Oscar
O
Boccadoro
Mario
M
Tarella
Corrado
C
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D015321:Gene Rearrangement; D006801:Humans; D007143:Immunoglobulin Heavy Chains / Q000235:genetics*; D008224:Lymphoma, Follicular / Q000175:diagnosis; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000188:drug therapy* / Q000235:genetics*; D016133:Polymerase Chain Reaction; D011446:Prospective Studies; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics*; D014178:Translocation, Genetic
D007143:Immunoglobulin Heavy Chains; D019253:Proto-Oncogene Proteins c-bcl-2