Lymphocytosis occurred and persisted in many dasatinib-treated patients in all phases of CML and its presence was associated with higher response rates, significantly longer response durations, and increased overall survival, suggesting an immunomodulatory effect. This according to a study of 1,402 dasatinib-treated patients with newly diagnosed chronic myeloid leukemia in chronic phase (CML-CP) who were refractory/intolerant to imatinib, or who were with CML in accelerated or myeloid blast phase. Researchers found:

• Lymphocytosis developed in 32% to 35% of patients and persisted for >12 months; an effect not seen in imatinib-treated patients.

• Dasatinib-treated patients in all stages of CML who developed lymphocytosis were more likely to achieve a complete cytogenetic response.

• Patients who had CMP-CP with lymphocytosis were more likely to achieve major and deep molecular responses.

• Progression-free and overall survival rates were significantly longer in patients with CML-CP who were refractory/intolerant to imatinib and had lymphocytosis.

• Pleural effusions developed more commonly in patients with lymphocytosis.

Citation: Schiffer CA, Cortes JE, Hochhaus A, et al. Lymphocytosis after treatment with dasatinib in chronic myeloid leukemia: Effects on response and toxicity. [Published online ahead of print March 21, 2016]. Cancer. doi:10.1002/cncr.29933.