I. Anemia secondary to lung cancer lesions is more complicated. Relevant studies have shown that lung cancer lesions are the root cause of anemia. Through direct invasion of bone marrow or metastasis, it destroys hematopoietic cells, inhibits hematopoietic function and controls the barrier of immature cell release, resulting in a decrease of peripheral Hb and RBC. Coughing up blood The prolonged hemoptysis caused by lung cancer can also cause chronic blood loss, thus causing hemorrhagic anemia; the side effects of lung cancer chemotherapy can also cause anemia due to loss of appetite and inadequate intake, resulting in malnutrition and the consumption of nutrients in the body. Cancer cells multiply in large numbers, causing the lack of hematopoietic materials such as folic acid, which makes RBC production difficult; the malignant proliferation of cells reduces normal cells, leading to anemia. At the same time, chemotherapy drugs are also inhibiting bone blood, making RBC production difficult by the mechanism of blocked erythropoietin production and inhibited proliferation of young red blood cells. In particular, platinum in chemotherapy drugs may damage human renal tubular cells, leading to a decrease in endogenous erythropoietin (EPO).