title: Molecular responses of late chronic phase chronic myeloid leukemia patients after achieving complete cytogenetic responses with imatinib treatment: a 6-year follow-up.
abstract: 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.
authors.affiliation: Institute of Hematology, People's Hospital of Peking University, 11 Xi-zhi-men South Street, Beijing 100044, China.
authors.forename: YaZhen
authors.initials: Y
authors.lastname: Qin
authors.forename: Bin
authors.initials: B
authors.lastname: Jiang
authors.forename: Qian
authors.initials: Q
authors.lastname: Jiang
authors.forename: Hao
authors.initials: H
authors.lastname: Jiang
authors.forename: JinLan
authors.initials: J
authors.lastname: Li
authors.forename: Yan
authors.initials: Y
authors.lastname: Zhang
authors.forename: HongHu
authors.initials: H
authors.lastname: Zhu
authors.forename: LingDi
authors.initials: L
authors.lastname: Li
authors.forename: ShanShan
authors.initials: S
authors.lastname: Chen
authors.forename: YanRong
authors.initials: Y
authors.lastname: Liu
authors.forename: XiaoJun
authors.initials: X
authors.lastname: Huang
mesh_terms: 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
chemical_list: D000970:Antineoplastic Agents; D001549:Benzamides; D010879:Piperazines; D011743:Pyrimidines; D000068877:Imatinib Mesylate; D016044:Fusion Proteins, bcr-abl