This disclosure relates to methods of selecting a subset of subjects having a hematological disorder and treating the selected group with a PI3K-delta inhibitor. In particular, the methods disclose evaluating levels of characteristic chemokine biomarkers, such as CCL2, CCL3, CCL4, CCL5, CXCL13, CCL17, CCL22, or TNF-alpha to select subjects that would have a greater chance of benefiting from treatment with a PI3K-delta inhibitor. The PI3K-delta inhibitors disclosed in this application are a type of quinazolinone-purinyl family of compounds.