Molecular responses of late chronic phase chronic myeloid leukemia patients after achieving complete cytogenetic responses with imatinib treatment: a 6-year follow-up.
To explore the long-term efficacy of imatinib to chronic myeloid leukemia, a total of 46 late chronic phase (CP) patients were assessed after achieving complete cytogenetic response (CCyR). The median duration of imatinib treatment was 68 (61-74) months. Two hundred fifty-three bone marrow samples were detected BCR-ABL messenger RNA (mRNA) levels by TaqMan-based real-time quantitative reverse transcription-polymerase chain reaction. The median time when CCyR was first achieved was eight (3-72) months. Thirty-four patients achieved major molecular response (MMoR), and their median time when MMoR was first achieved was 35 (3-65) months. More patients achieving CCyR within 18 months obtained MMoR than those after 18 months (85% vs 42%, p = 0.006). One patient progressed into blastic crisis, and four patients suffered cytogenetic relapse later. The estimated 6-year event-free survival (EFS) rate of all patients was 81%. The BCR-ABL mRNA levels at the time of first CCyR of relapsed patients were significantly higher than those in continuous CCyR (p = 0.011). The 6-year estimated EFS rate of MMoR patients was significantly higher than that of non-MMoR patients (100% vs 44%, p = 0.0001). Achieving CCyR within 18 months had a higher probability of achieving MMoR within 6 years. The 6-year estimated EFS rate was significantly higher for patients achieving CCyR within 12 months than those after 12 months (97% vs 55%, p = 0.05). The time when MMoR was first achieved did not affect 6-year estimated EFS. Therefore, imatinib could induce most late CP patients to achieve long-term durable responses after achieving CCyR. Both the time when CCyR was first achieved and the depth of BCR-ABL reduction after CCyR are relevant to long-term EFS.
Qin
YaZhen
Y
Institute of Hematology, People's Hospital of Peking University, 11 Xi-zhi-men South Street, Beijing 100044, China.
Jiang
Bin
B
Jiang
Qian
Q
Jiang
Hao
H
Li
JinLan
J
Zhang
Yan
Y
Zhu
HongHu
H
Li
LingDi
L
Chen
ShanShan
S
Liu
YanRong
Y
Huang
XiaoJun
X
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D001549:Benzamides; D018572:Disease-Free Survival; D005500:Follow-Up Studies; D016044:Fusion Proteins, bcr-abl / Q000235:genetics; D006801:Humans; D000068877:Imatinib Mesylate; D015466:Leukemia, Myeloid, Chronic-Phase / Q000188:drug therapy / Q000503:physiopathology; D010879:Piperazines / Q000627:therapeutic use*; D011743:Pyrimidines / Q000627:therapeutic use*; D012008:Recurrence
D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D016044:Fusion Proteins, bcr-abl