Cancer
Thrombocytosis can happen as a secondary effect of some cancers [3]. This type of elevated platelet count is known as paraneoplastic thrombocytosis. It is likely to happen in people who have solid tumors such as lung cancer, ovarian cancer, liver cancer, and colorectal cancer.
Chronic myelogenous leukemia [4] can also cause an increase in the platelet count in the body. This is a rare type of cancer that begins in the bone marrow and progresses very slowly. The bone marrow is where the cells of the blood are produced. An alteration in its normal function can change the production rate of platelets.