OVERVIEW
Anemia due to malignant tumors refers to anemia caused by various malignant tumors other than hematopoietic tissues. The type and degree of anemia varies according to the type of malignant tumor, the course of the disease, and the method of treatment. Clinical manifestations vary with the type of tumor, site of occurrence and degree of metastatic spread. Anemia of digestive tract tumors is found earlier and the symptoms are more serious, which is often related to its tendency to cause hemorrhage and combined with nutrient absorption disorder, and even anemia is the first symptom of the tumor and attracts attention.
Etiology
Tumor-associated anemia is one of the common diseases associated with malignant tumors, and its occurrence has various causes, such as the factors of the disease itself, such as blood loss and bone marrow invasion; anti-tumor treatment-associated anemia, such as myelosuppression after chemotherapy and radiation therapy for tumors, and so on.
Pathology
1. Peripheral blood
Positive cellular, positive pigment anemia, reticulocytes increase, severe anemia can be seen anomalous and stippling red blood cells, such as the combination of microangiopathic anemia, the number of anomalous red blood cells increased significantly. Patients with digestive tract tumors are often combined with blood loss, and their anemia manifests as microcytic and hypochromic anemia. When the tumor metastasizes to the bone marrow, the peripheral blood may show juvenile red and juvenile granulocytes, and the anemia is moderately severe. Normal or increased white blood cells are due to the tumor can stimulate the increase of neutrophils. Platelet count is normal or decreased.
2. Bone marrow
Pay attention to the tumor cells. Cancer cells tend to gather in several groups or form clusters, and the common features of their morphology are: (1) the cells and nuclei are larger, with thicker staining; (2) polymorphism; (3) the ratio of cytosolic/cytoplasmic nuclei increases; (4) the nuclei are large, unequal in number, and anomalous in nature. However, the morphology of primitive neuroblastoma cells resembles that of progranulocytes or prolymphocytes, and there is no tendency of aggregation and clustering, the cytomembrane is easy to be broken, and it becomes a naked nucleus, and the cytoplasm contains mucus, and the reaction of glycogen is positive. In tumor-induced ferrocytic anemia, there is increased iron staining of young erythrocytes in the bone marrow, with >15% ring-type ferrocytes. Often there is necrosis of bone marrow cells.
3. Decreased serum iron
Total iron binding capacity is normal or slightly decreased, iron saturation is reduced, in line with the iron metabolism characteristics of patients with anemia of chronic disease, but if the combination of hemorrhage or obvious hemolysis, there are corresponding iron metabolism characteristics. Most of the red blood cell survival time is slightly shortened.
Symptoms
Clinical manifestations vary with tumor type, site of occurrence and degree of metastatic spread. Anemia of digestive tract tumors is found earlier and the symptoms are more serious, which is often related to its tendency to cause bleeding and combined with nutritional absorption disorder, and even anemia is the first symptom of the tumor and attracts attention. On the contrary, the anemia of lung cancer is found later, the anemia is mild, and the anemia symptoms are often covered by the tumor itself. Generally, anemia in late stage of tumor is more serious than the early stage, which is mostly caused by chemotherapy or radiotherapy-induced bone marrow suppression, cancer bone marrow metastasis, patients’ low immunity and secondary infection, malabsorption of nutrients and other comprehensive factors.
Examination
X-ray, CT, ultrasound, electrocardiogram, biochemistry and other examinations are feasible.
Diagnosis
X-ray, CT, ultrasound, electrocardiogram, biochemistry and other examinations can be selected according to the patient’s condition, clinical manifestations, symptoms and signs for diagnosis.
Treatment
1. Anemia caused by tumor mainly depends on tumor treatment. If the tumor is cured or the therapeutic effect reaches clinical remission after surgical operation, chemotherapy, radiotherapy and biological treatment, the anemia can be significantly improved or even disappeared.2. If the anemia is serious in the course of tumor treatment, it can be treated by blood transfusion, or erythropoietin can be injected subcutaneously every other day once, and the red blood cells and hemoglobin can be increased and the symptoms of anemia can be alleviated in 4~6 weeks. For patients with tumor-induced anemia that is not associated with nutritional deficiency causes, supplementation with iron, folic acid and vitamin B12. hormones may be temporarily effective in patients with combined autoimmune hemolytic anemia.