All 6 patients experienced responses of splenomegaly and/or symptoms but leukocytosis and/or thrombocytosis required addition of hydroxyurea in 3/6 patients whereas dosage reductions due to hematotoxicity was not necessary in any of the patients treated with an ABL-TKI and ruxolitinib, This contrasts with the scarce literature on combination treatment, where anemia and/or thrombocytopenia during combination treatment were frequently observed. The gene discussed is ABL1; the disease is thrombocytosis disease.