Leukemia is the main term that is used to define 4 different types of blood cancer. Common ground of those 4 different types of leukemia is the origination from a cell in the bone marrow. The cell undergoes a change and transforms into a type of leukemia cell. Etiology of many leukemia cases is not known. When bone marrow cell undergoes “leukemic” transformation, it is divided to many cells and proliferates faster, lives longer and creates a larger cell population – all pave the way to the disease - in comparison with healthy cells. Some signs and symptoms of leukemia can be confused with signs of many common diseases. Definitive diagnosis requires specific blood tests and bone marrow analyses. Most common symptoms of leukemia include fatigue, tiredness, exertional dyspnea, pallor, mild fever or night sweating, poor wound healing, massive bleeding, idiopathic black and blue spots on skin (bruises), subcutaneous red spots identical to pinhead in size and bone pain as well as arthralgia (i.e., knees, hips or shoulders). Treatment and outcomes depend on type and subtype of the leukemia. Although recovery rate up to 75% is possible with multi-agent therapies, there are some concerns about success rates of therapies that may vary from 10% to 90% depending on type of leukemia. Aim of therapy in leukemia is “complete remission”. This means absence of any sign of the disease after therapy and complete restoration of healthy status. Recently, ever increasing number of patients with leukemia achieve complete remission for minimum 5 years after therapy.
“Leukemia” is the general term that is used to define 4 different types of blood cancer, namely acute lymphocytic (lymphoblastic) leukemia (ALL), acute myelogeneous (myeloid) leukemia (AML), chronic lymphocytic leukemia (CLL) and chronic myeloid leukemia (CML). For each type of leukemia, it is necessary to know how patient is affected and how the condition is treated. Common ground of those 4 different types of leukemia is the origination from a cell in the bone marrow. The cell undergoes a change and transforms into a type of leukemia cell.
Bone marrow is the spongious tissue that is located in bones and is responsible for producing blood cells and lymphocytes. “Stem cell” is the precursor structure of all blood cells. There are various types of cells that are produced in bone marrow, such as red blood cells, platelets, lymphocytes and many other types of white blood cells. After those cells mature in bone marrow, they are released from the bone marrow to the blood circulation.
Bone marrow meets functions of two organs in a single organ. The first one is the organ that produces blood cells. It is where myeloid leukemia develops. The second one is the organ that produces lymphocytes and is a part of immune system. It is where lymphocytic leukemia develops.
If a carcinogenic transformation develops in bone marrow cell that is transformed into “lymphocytes”, type of leukemia is called as “lymphocytic” or “lymphoblastic”. If a cellular change develops in bone marrow cells that are transformed into red blood cells, some types of white blood cells and platelet, leukemia is referred as “myelogeneous” or “myeloid”. Development of disease and treatment modality vary in each type of leukemia.
“Acute lymphocytic leukemia” and “acute myeloid leukemia” originate from young cells that are known as “lymphoblast” and “myeloblast”, respectively. Those cells are sometimes called as “blast”. Leukemia progresses rapidly, if left untreated. Blast cells are absent or very scarce in “chronic” leukemia. Usually, “chronic lymphocytic leukemia” and “chronic myeloid leukemia” progress slower than acute leukemia.
Treatment and outcomes depend on type and subtype of the leukemia. Aim of therapy in leukemia is “complete remission”. This means absence of any sign of the disease after therapy and complete restoration of healthy status. Recently, ever increasing number of patients with leukemia achieve complete remission for minimum 5 years after therapy.
For patients with acute leukemia, treatment should be immediately started. Treatment is usually started with chemotherapy at hospital settings. First stage of therapy is referred as “induction therapy”. Even if patient is in remission, it may be necessary to prolong therapy at inpatient settings. This prolonged therapy period is referred as “consolidation” or “post-induction” therapy. This part of therapy may involve combination of stem cell transplantation (or sometimes referred as “bone marrow transplantation”) and chemotherapy or chemotherapy alone.
Patients with CML should be started on therapy immediately after final diagnosis is made. Treatment is usually started with preparations that contain imatinib mesylate as active ingredient. Those drugs are received. Preparations with imatinib mesylate do not heal CML. However, CML can be kept under control in many patients as long as it is used. In some patients, imatinib mesylate can be replaced with other drugs that contain dasatinibe as active ingredient.
Allogeneic stem cell transplantation is now the only therapeutic modality for CML. This therapy shows highest success in young patients. This therapy can be considered for patients who are aged 60 years or older and have a matched donor. Allogeneic transplantation is a high-risk process. Studies are in progress that investigate whether better long-term outcomes are obtained for CML patients with medication therapy or with transplantation.
Some patients with CLL do not require long-term therapy after diagnosis. Patients who require therapy receive chemotherapy alone or combination of chemotherapy and monoclonal antibody. Allogeneic stem cell transplantation is a therapeutic option for some patients. Patients with AML, ALL, CML and CLL in remission should regularly visit their doctors for examination and blood testing. Bone marrow testing can be occasionally required. If disease-free status can be maintained, your doctor may offer prolonging intervals between visits.