This invention is based, at least in part, on the finding that certain microRNAs (miRNAs) are expressed at higher or lower levels in circulating exosonies or peripheral blood of subjects with hematological malignancies compared to the level of expression in subjects who do not have the hematological malignancy. In addition, this invention is based, at least in part, on the finding that certain miRNAs are differentially expressed at different stages of a hematological malignancy permitting identification of the stage of the hematological malignancy in a subject. The differential expression of miRNAs at different stages of a hematological malignancy also permits determination of the effectiveness of treatments administered to a subject at the particular stage of the hematological malignancy.
