As with many cancers, the cause of<unk>  is unknown. Exposure to tobacco smoke, ionizing radiation, or industrial chemicals (with the possible exception of diesel) does not appear to increase the risk of developing it. Farming and gardening correlate with an increased risk of<unk>  development in some studies which does not necessarily imply causation. A 2011 study identified somatic BRAF V600E mutations in all 47<unk>  patients studied, and no such mutations in the 193 peripheral B-cell lymphomas/leukemias other than<unk> . The U.S. Institute of Medicine (IOM) found a correlation which permits an association between exposure to herbicides and later development of chronic B-cell leukemias and lymphomas in general. The IOM report emphasizes that neither animal nor human studies indicate an association of herbicides with<unk>  specifically. However, the IOM extrapolated data from chronic lymphocytic leukemia and non-Hodgkin lymphoma to conclude that<unk>  and other rare B-cell neoplasms may share this risk factor. As a result of the IOM report, the U.S. Department of Veterans Affairs considers<unk>  an illness presumed to be a service-related disability Human T-lymphotropic virus 2 (HTLV-2) has been isolated in a small number of patients with the variant form of<unk> . In the 1980s, HTLV-2 was identified in a patient with a T-cell lymphoproliferative disease; this patient later developed<unk> , but HTLV-2 was not found in the<unk>  cell clones. There is no evidence that HTLV-II causes any sort of hematological malignancy, including<unk> .
Hairy cell leukemia
Chronic lymphocytic leukemia
Prolymphocytic leukemia
B-cell leukemia
T-lymphoblastic leukemia/lymphoma
T-cell leukemia
Large granular lymphocytic leukemia
Leukemoid reaction