From the Research
Thrombocytosis in cancer patients is primarily caused by the body's inflammatory response to malignancy, with cancer cells releasing inflammatory cytokines that stimulate the liver to produce thrombopoietin, leading to increased platelet production in the bone marrow 1. The causes of thrombocytosis in cancer patients can be multifactorial, including:
- The body's inflammatory response to malignancy, with cancer cells releasing inflammatory cytokines such as interleukin-6 (IL-6), interleukin-1 (IL-1), and tumor necrosis factor-alpha (TNF-α) 1
- Some tumors directly producing thrombopoietin or other growth factors that stimulate platelet production
- Certain cancer types being more commonly associated with thrombocytosis, including lung, gastrointestinal, ovarian, and breast cancers
- Chemotherapy and other cancer therapies increasing the risk of thrombosis, with some agents such as tamoxifen, immunomodulatory imide drugs, and bevacizumab having a higher risk of thrombotic events 2 The presence of thrombocytosis in cancer patients is clinically significant as it increases the risk of thrombotic events such as deep vein thrombosis and pulmonary embolism, and in some cases, paraneoplastic thrombocytosis can be an early marker of malignancy or indicate disease progression. Treatment typically focuses on addressing the underlying cancer rather than directly targeting the elevated platelet count, though antiplatelet or anticoagulant therapy may be considered in patients at high risk for thrombotic complications 1. It's worth noting that the most recent study 3 discusses the role of growth factors in managing chemotherapy-induced cytopenia, but it does not directly address the causes of thrombocytosis in cancer patients. Therefore, the recommendation is based on the highest quality study available 1.