Introduction of Hematologic Cancer
Hematologic malignancies are tumors that affect the blood, bone marrow, lymph, and lymphatic system. It includes three kinds of cancer type, such as leukemia, lymphoma, and myeloma.
Leukemia is a common malignant tumor of the hematopoietic system. In 1845, leukemia is discovered by Bennett and Virchow. They blood from a patient with anemia and hepatosplenomegaly. After a period of time, the blood is stratified to produce yellow-white substance, all of which was white blood cells, so it was called leukemia. The cause of leukemia is that hematopoietic tissue does not work properly due to DNA mutations in hematopoietic cells. The manifestation of leukemia is that one or more blood cells in the hematopoietic system such as bone marrow and lymph nodes become cancerous, resulting in uncontrolled proliferation, differentiation disorder, and blocked apoptosis, so that hematopoietic cells stop at different stages of cell maturation. In the bone marrow and other hematopoietic tissues, the cancerous cells proliferate in a large amount and infiltrate various organ tissues in the body, resulting in inhibition of normal hematopoietic cells. It is often characterized by fever, hemorrhage, anemia and the swelling of liver, spleen and lymph follicle. There are two classification methods for leukemia in clinical practice. The first is divided into acute and chronic according to the natural disease course and the maturity of cells. The second is divided into granulocytes, lymphocytes and monocytes by cell type. Depending on the survey, acute leukemia accounts for 70% of leukemia patients. Among them, acute myeloid leukemia is the most.
Lymphoma is a collection of blood cancers that develop from lymphocytes (a type of white blood cell). There are dozens of subtypes of lymphomas. The two main categories of lymphomas are Hodgkin's lymphomas (HL) and the non-Hodgkin lymphomas (NHL). About 90% of lymphomas are non-Hodgkin lymphomas. Lymphomas and leukemia are part of the broader group of tumors of the hematopoietic and lymphoid tissues. Risk factors for Hodgkin lymphoma include infection with Epstein-Barr virus and a history of the disease in the family. Risk factors for common types of non-Hodgkin lymphomas include autoimmune diseases, HIV/AIDS, infection with human T-lymphotropic virus, immunosuppressant medications, and some pesticides. Eating large amounts of red meat and tobacco smoking may enhance the risk. The diagnosis of lymphoma is usually lymph node biopsy. The criterion is if enlarged lymph nodes are found. In addition, blood, urine, and bone marrow testing may be helpful in the diagnosis. Medical imaging may then be done in order to determine if and where the cancer has spread, and lymphoma most often spreads to the lungs, liver, and brain. Signs and symptoms may include enlarged lymph nodes, fever, drenching sweats, unintended weight loss, itching, and constantly feeling tired. The enlarged lymph nodes are generally painless, and the sweats are most frequent at night.
Myeloma is a cancer of plasma cells, a type of white blood cell normally responsible for producing antibodies. In general, no symptoms are seen initially. Bone pain, bleeding, frequent infections, and anemia may occur along with the condition progress, even include amyloidosis. The cause of myeloma is unknown. According to previous studies, risk factors include drinking alcohol, obesity, radiation exposure, family history, and certain chemicals. The mechanism involves abnormal plasma cells producing abnormal antibodies which can cause kidney problems and overly thick blood. The plasma cells can also form a mass in the bone marrow or soft tissue. When only one mass is present, it is known as a plasmacytoma while more than one is known as multiple myeloma. Multiple myeloma is diagnosed based on blood or urine tests finding abnormal antibodies, bone marrow biopsy finding cancerous plasma cells, and medical imaging finding bone lesions. Another common finding is high blood calcium levels.
Diagnosis and Treatment of Hematologic Cancer
The diagnosis of leukemia is for the most part based on complete blood counts and bone marrow examination followings of the symptoms. Nevertheless, blood tests do not always illustrate that a person has leukemia, especially in the early stages of the disease or during remission. Additionally, a lymph node biopsy can be performed to diagnose certain types of leukemia in certain situations. Except for some direct diagnoses, there are several diagnoses to help the treatment of leukemia. Such as blood chemistry tests can be used to detect the degree of liver and kidney damage or the effects of chemotherapy on the patient. Besides, X-ray, MRI and ultrasound can use to test other damage due to leukemia. Despite the use of these methods to diagnose whether or not a patient has leukemia, many individuals have not been diagnosed since quite a few of symptoms are vague, non-specific, and can refer to other diseases. Leukemia is treated with pharmaceutical medication, typically combined into a multi-drug chemotherapy regimen. Some are also treated with radiation therapy. But so far, bone marrow transplantation is still the most effective means of treating leukemia.
Lymphoma is definitively diagnosed by a lymph node biopsy, meaning a partial or else total excision of lymph node examined under the microscope. This examination reveals histopathological features that may indicate lymphoma. Prognoses and treatments are different for Hodgkin lymphoma (Hodgkin lymphoma is marked by the presence of a type of cell called the Reed-Sternberg cell.) and Non-Hodgkin lymphomas (Non-Hodgkin lymphomas, which are defined as being all lymphomas except Hodgkin lymphoma, are more common than Hodgkin lymphoma.). The treatment also depends on the grade of tumor. Hodgkin lymphoma typically is treated with radiotherapy alone, as long as it is localized. For non-Hodgkin lymphomas, there are 2 sorts of treatment. First, in low-grade lymphomas, watchful waiting is often the initial course of action. As the therapy may not be the benefit of pathogenic condition. Second, in high-grade lymphomas, there needs aggressive chemotherapy to treat the lymphoma.
In theory, multiple myeloma can produce all classes of immunoglobulin, but IgG paraproteins are most common, followed by IgA and IgM. IgD and IgE myeloma are very rare. In the process of diagnosis, the patient can be detected by blood tests and histopathology. In blood tests, quantitative measurements of the paraprotein (monoclonal protein, or M protein) and IgA, IgG and IgM (immunoglobulins) are necessary to establish a diagnosis and to monitor the disease. In histopathology, a bone marrow biopsy is usually performed to estimate the percentage of bone marrow occupied by plasma cells. This percentage is used in the diagnostic criteria for myeloma. Treatment for multiple myeloma is focused on therapies that decrease the clonal plasma cell population and consequently decrease the symptoms of disease. In addition to direct treatment of the plasma cell proliferation, bisphosphonates are routinely administered to prevent fractures; they have also been observed to have a direct anti-tumor effect even in patients without known skeletal disease. If needed, red blood cell transfusions or erythropoietin can be used for management of anemia.