Hammersmith score application identifies chronic myeloid leukemia patients with poor prognosis before treatment with second-generation tyrosine kinase inhibitors

In this study, we confirm the validity of the proposed Hammersmith score, which identifies three risk categories of patients and establish its strength on a large group of 128 chronic myeloid leukemia patients treated with second-generation tyrosine kinase inhibitors (TKIs) after being resistant to imatinib. Sixty-one patients were identified as good risk group, 27 patients as intermediate risk group, and 40 patients as poor risk group. The 1-year cumulative incidence of complete cytogenetic response was 73% in good risk patients, 40% in intermediate risk patients, and 22% in poor risk patients (P = 0.0001). Event-free survival at 3-year was 89% in good risk group, 70% in intermediate group, and 54% in poor risk group (P = 0.0001); the estimated 3-year progression-free survival was 95% in good risk category, 93% in intermediate risk category, and 87% in poor risk category (P = 0.05). Kaplan-Meier estimated that the 3-year overall survival was 100% in good risk category, 93% in intermediate risk category, and 82% in poor risk category (P = 0.04). In conclusion, some prognostic factors before starting second-generation TKIs might predict cytogenetic response and outcome. The so-called Hammersmith score was not yet validated in large series of patients: we demonstrated that this score is able to discriminate patients at high risk of failure and consequent progression before treatment with second-generation TKIs.