Assessment of the response to imatinib in chronic myeloid leukemia patients--comparison between the FISH, multiplex and RT-PCR methods.
OBJECTIVE
The objective of this study was to evaluate the kinetics of molecular response in chronic myeloid leukemia (CML) patients treated with imatinib and to compare between the fluorescent in situ hybridization (FISH), multiplex and real-time quantitative RT-PCR (RQ-PCR) methods with this respect.


METHODS
Molecular follow-up was carried out on 24 CML patients treated with imatinib. FISH analysis was performed according to the standard protocol. For RT-PCR the multiplex and RQ-PCR methods were used.


RESULTS
Sixty-three percent and 52% of the patients achieved complete remission according to FISH and multiplex RT-PCR analyses, respectively. Seventy-five percent of the patients achieved remission within the first year of treatment. In 83% of the cases the FISH and RT-PCR results were concordant. RQ-PCR analysis was carried out on 32 of the 41 samples negative by multiplex RT-PCR but only nine were negative. All samples with a BCR-ABL/ABL ratio below 2% were also negative by FISH. There was an excellent correlation between the RQ-PCR and the FISH tests.


CONCLUSIONS
Molecular remission according to FISH and multiplex RT-PCR can be achieved by imatinib within 1 yr of therapy. There is a good correlation between the FISH, multiplex and RQ-PCR results in terms of the kinetics of disappearance of the BCR-ABL transcript and the predictability of each method for the other. Although RQ-PCR is the most sensitive method for molecular follow-up, FISH and multiplex RT-PCR can be used as complementary tools, at least during the early period of treatment.
Raanani
Pia
P
The Institute of Hematology, The Chaim Sheba Medical Center, Tel-Hashomer, Israel. praanani@012.net.il
Ben-Bassat
Isaac
I
Gan
Shlomit
S
Trakhtenbrot
Luba
L
Mark
Ziva
Z
Ashur-Fabian
Osnat
O
Itskovich
Svetlana
S
Brok-Simoni
Frida
F
Rechavi
Gideon
G
Amariglio
Ninette
N
Nagler
Arnon
A
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D005260:Female; D006801:Humans; D000068877:Imatinib Mesylate; D017404:In Situ Hybridization, Fluorescence / Q000379:methods*; D015464:Leukemia, Myelogenous, Chronic, BCR-ABL Positive / Q000188:drug therapy* / Q000235:genetics / Q000473:pathology; D008297:Male; D008875:Middle Aged; D010879:Piperazines / Q000627:therapeutic use*; D011743:Pyrimidines / Q000627:therapeutic use*; D012074:Remission Induction; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*
D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate