Leukemia is cancer that starts in the tissue that forms blood. To understand cancer, it helps to know how normal blood cells form.
Normal Blood Cells
Most blood cells develop from cells in the bone marrow called stem cells.
Bone marrow is the soft material in the center of most bones.
Stem cells mature into different kinds of blood cells. Each kind has a
special job:
White
blood cells help fight infection. There are several types of white blood cells.
Red
blood cells carry oxygen to tissues throughout the body.
Platelets help form
blood clots that control bleeding.
White blood cells, red blood cells, and platelets are made from stem cells as
the body needs them. When cells grow old or get damaged, they die, and new cells
take their place.
The picture below shows how stem cells can mature into different types of
white blood cells. First, a stem cell matures into either a myeloid stem cell or
a lymphoid stem cell:
A myeloid stem cell matures into a myeloid blast. The blast can form a red
blood cell, platelets, or one of several types of white blood cells.
A lymphoid stem cell matures into a lymphoid blast. The blast can form one of
several types of white blood cells, such as B cells or T cells.
The white blood
cells that form from myeloid blasts are different from the white blood cells
that form from lymphoid blasts.
Leukemia Cells
In a person with leukemia, the bone marrow makes abnormal white blood cells.
The abnormal cells are leukemia cells.
Unlike normal blood cells, leukemia cells don't die when they should. They
may crowd out normal white blood cells, red blood cells, and platelets. This
makes it hard for normal blood cells to do their work.
Anemia is the condition of having less than the normal number of red blood cells or less than the normal quantity of hemoglobin in the blood. The oxygen-carrying capacity of the blood is, therefore, decreased.
Lymph nodes help the body's immune system fight infections. Causes of swollen lymph nodes (glands) may include infection (viral, bacterial, fungal, parasites). Symptoms of swollen lymph nodes vary greatly. They can sometimes be tender, painful or disfiguring. The treatment of swollen lymph nodes depends upon the cause.
Systemic lupus erythematosus is a condition characterized by chronic inflammation of body tissues caused by autoimmune disease. Lupus can cause disease of the skin, heart, lungs, kidneys, joints, and nervous
system. When only the skin is involved, the condition is called discoid lupus.
When internal organs are involved, the condition is called systemic lupus
erythematosus (SLE).
Non-Hodgkin's lymphoma is cancer of the lymphatic system, a vital part of the body's immune system. Symptoms include swollen lymph nodes, fever, night sweats, coughing, weakness, chest pain, unexplained weight loss, and abdominal pain. Treatment depends on which type of non-Hodgkin's lymphoma you have, the stage of the cancer, your age, how fast the cancer is growing, and whether you have other health problems.
Carpal tunnel syndrome is a condition in which irritation of the wrist's median nerve causes tingling and numbness of the thumb, index, and the middle fingers. This condition is known as tarsal tunnel syndrome in the ankles and feet. Treatment of carpal tunnel syndrome depends on the severity of the symptoms and the nature of any disease that might be causing the symptoms.
Hodgkin's disease is a cancer of the lymphatic system with symptoms that include unexplained, recurring fevers, unexplained weight loss, itchy skin, and painless swelling of the lymph nodes in the neck, underarm, and groin. Treatment for adult Hodgkin's disease depends on the staging of the disease, the lymph nodes' size, and the health of the patient.
The spleen enlarges if it is asked to do excessive work in filtering or manufacturing blood cells, if there is abnormal blood flow to it, or if it is invaded with abnormal cells or deposits. Symptoms of an enlarged spleen may include weakness and fatigue, easy bleeding, and poor white blood cell function. Treatment of an enlarged spleen is focused toward the cause of the splenomegaly. Surgery may be required to remove the spleen.
Cancer is a disease caused by an abnormal growth of cells, also called malignancy. It is a group of 100 different diseases, and is not contagious. Cancer can be treated through chemotherapy, a treatment of drugs that destroy cancer cells.
Down syndrome is a chromosomal disorder that results in the presence of an additional third chromosome 21, also referred to as trisomy 21. Most individuals with Down syndrome have widely recognizable physical characteristics. The severity of Down syndrome ranges from mild to severe. Diagnostic testing for Down syndrome include amniocentesis, chorionic villus sampling, and percutaneous umbilical cord sampling. The most common risk factor for Down syndrome is a woman's age.
Thrombocytopenia refers to a decreased number of platelets in the blood. There are many causes of thrombocytopenia such as decreased platelet production (viral infections for example rubella, mumps, chickenpox, hepatitis C, and HIV); increased platelet destruction or consumption (for example sulfonamide antibiotics, heparin, blood transfusions, and lupus); or increased splenic sequestration (enlarged spleen due to conditions for example liver disease, blood cancers, and more). Treatment of thrombocytopenia depends on the cause.
Eye floaters are deposits or condensation that forms in the eye's vitreous humor. These deposits cast shadows on the retina, and as the eye moves, the deposits shift position, making it appear as though the shadows are moving or floating.
Pericarditis is the inflammation of the pericardial sac that surrounds the heart. The causes of pericarditis include injury from heart attack, heart surgery, trauma; viral or fungal infection, HIV, tumors, mixed connective tissue disease, metabolic disease, medication reactions, or idiopathic. Treatment for pericarditis is generally medication, however, sometimes surgery is necessary.
Though it's difficult to say why some people develop cancer while others don't, research shows that certain risk factors increase a person's odds of developing cancer. These risk factors include growing older, family history of cancer, diet, alcohol and tobacco use, and exposure to sunlight, ionizing radiation, certain chemicals, and some viruses and bacteria.
Eosinophilic fasciitis is a skin disease that causes thickening and inflammation of the skin and fascia. Symptoms include redness, warmth, and hardening of the skin, as well as occasional tissue and joint pain. Treatment for eosinophilic fasciitis aims to eliminate inflammation through the use of aspirin, NSAIDs, and cortisone. Aggressive forms of eosinophilic fasciitis may require the use of immune suppression medications.
Stem cells are referred to as undifferentiated cells due to the fact that they have not yet committed to a developmental path to form specific organ tissue. There are a variety of types of stem cells to include embryonic, fetal, adult peripheral blood, umbilical cord, and induced pluripotent stem cells.
Childhood acute lymphoblastic leukemia is the most common type of cancer in children. Symptoms and signs include fever, easy bruising, bone or joint pain, weakness, loss of appetite, and painless lumps in the neck, underarm, stomach, or groin. Treatment depends upon staging and may include chemotherapy, radiation, or stem cell transplant.