OBJECTIVETo evaluate the long-term prognosis of CML patients whose BCR-ABL transcript level was warning and best response at 12 months of treatment with tyrosine kinase inhititor (TKI), and to investigate the factors affecting therapeutic efficacy and prognosis.

METHODSThe clinical data of patients with newly diagnosed CML were analyzed retrospectively. According to BCR-ABL transcript level, the 80 patients were divided into group A and group B, the patients with BCR-ABL >0.1% and ≤ 1% (warning response) were entolled in group A, and the patients with BCR-ABL ≤ 0.1% (best response) were enrolled in group B as control. The ratio of patients with main molecular response (MMR) and deep molecular response (DMR), as well as aquistation rate and cummulative rate of MR (DMR) at specified fine points in 2 groups were compared, the independent risk factors affecting the therapeutic efficacy and prognosis were analyzed.

RESULTSThe MMR and MR of the B group at 15, 18 and 24 months after TKI treatment were significantly higher than those of the A group, and the patients in the B group reached MR faster. In the 3 months, 6 months and 12 months after the demarcation point (TKI 12 months), the A group was much less easy to obtain MR (P<0.05) than the B group. Through survival analysis, there were more patients in the B group than the A group at different time points to reach MR, and the difference was statistically significant (P<0.01). The single factor analysis showed that the splenomegaly (below rib edge)> 10cm (P<0.01) and lactate dehydrogenase > 400 U/L (P<0.05) were the long-term warning factors for patients. Multivariate analysis showed that the size of the spleen was an independent factor (P<0.01) to affect the prognosis of the patients who had been warned for 12 months.

CONCLUSIONPatients at 12 months warning effect are slower and less easier to get DMR, which has a poor long-term prognosis. The size of the spleen in the patient at warning for 12 months of treatment effect can predict the relatively poor long-term prognosis. For a patient with a 12 months response to the warning, an early replacement therapy is available on the basis of combining other factors..