Leukemia Leukemia is a cancer that starts to form from white blood cells (lymphocytes) in the bone marrow. The term “leukemia” is a general term that umbrellas four types of this cancer: acute myelogenous leukemia, acute lymphatic leukemia, chronic myelogenous leukemia, and chronic lymphocytic leukemia. Lymphocytic refers to cancerous activity that occurs in a type of marrow cell that forms lymphocytes, while the term myelogenous indicates cancerous changes taking place in marrow cells that form red blood cells, some white blood cells, and platelets. The distinction between chronic and acute leukemia lies in the presence of blast cells and the speed at which they progress. The term “acute” means that the leukemia can progress quickly and if not treated would probably be fatal within a few months. Also with acute leukemia, blast cells are present. Chronic leukemia has very few blast cells and progresses slower than acute leukemia. Asbestos Exposure and Leukemia While the carcinogenicity of asbestos is established and has been linked to cancers such as mesothelioma and lung cancer, recently it has been suspect in several other cancers such as leukemia. One study included two cases of individuals with acute myelogenous leukemia who had a long history of asbestos exposure. Scientists found significant numbers of asbestos bodies in the patients’ lungs and bone marrow. Conclusively, there is insufficient evidence to prove a causal link between asbestos exposure and leukemia; however the possibility of a connection is not out of the question. Currently the role of asbestos exposure in the development of leukemia requires further research. Another study documenting a connection between malignancy and asbestos exposure found that five of 10 cases of leukemia were related to asbestos exposure. In a 2005 study, the patient studied developed B-prolymphocytic leukemia/ lymphoma (B-PLL) and then rapidly developed malignant peritoneal mesothelioma. The study concluded that a concurrent development of these two diseases implied a possible causal relationship. After ruling out other factors, the authors noted that asbestos exposure was the sole possible connection to these cancers. The possibility of asbestos exposure relating to lymphoid diseases is found in asbestos fibers’ ability to reach lymph nodes and other elements of the immune system. Some studies have found evidence of this factor, while others have been inconclusive. Further analysis is needed to better understand a possible relationship.