What Is Myelofibrosis?
Myelofibrosis is a blood cancer of very rare occurrence. In this condition, the bone marrow is replaced by fibrous tissue. This fibrous tissue is known as scar tissue. Myelofibrosis is a chronic form of leukemia. This condition can also be classified as a myeloproliferative neoplasm. Myeloproliferative neoplasms are cancerous conditions in which white blood cells are produced in excess quantity in the bone marrow.
The bone marrow produces primitive red blood cells (RBCs), white blood cells (WBCs), and platelets. This later matures into their respective cells and their subtypes. In most types of blood cancers, the blood cells produced by the bone marrow are defective in nature and hence do not mature into their final shape and form. This could occur due to genetic mutations. The cells pass on the mutations to the new cells, also. With time, more and more abnormal cells are produced. The scar tissue that forms in the bone marrow results from the underlying inflammation due to the cells that have piled up. The scar tissue prevents the production of normal blood cells. Hence there is a cascading effect on the bone marrow.
What Are the Types of Myelofibrosis?
Myelofibrosis is of two types-
-
Primary Myelofibrosis: It is the type of myelofibrosis that occurs independently.
-
Secondary Myelofibrosis: This type of disorder occurs secondary to other blood disorders such as polycythemia and thrombocytosis. It constitutes about 20 % of the total occurrences.
What Is the Occurrence of Primary Myelofibrosis?
The occurrence of primary myelofibrosis is quite rare. It can affect both genders equally. It is more common in individuals above the age of 50 years. It may occur in children, but it is diagnosed in children less than three years of age.
What Causes Primary Myelofibrosis?
The exact cause for the occurrence of primary myelofibrosis is unknown. The underlying cause for the occurrence of this condition is a genetic mutation. The mutation causes changes in the genetic sequence and the protein structure of DNA. In myelofibrosis, it is believed that a protein called Janus-associated kinases (JAKs) is affected. JAKs regulate the production of blood cells from the bone marrow by passing signals about the production and differentiation of the cells. If these proteins are distorted, the blood cell-producing mechanism is also distorted.
What Are the Risk Factors for Primary Myelofibrosis?
The following can increase the risk of primary myelofibrosis:
-
If a person is over the age of 50 years.
-
If the person is affected with other blood conditions such as primary thrombocytosis and polycythemia vera.
-
Exposure to harmful chemicals such as benzene and toluene.
What Are the Effects of Myelofibrosis on the Body?
Abnormal blood cell production can cause various conditions, such as-.
-
Anemia: It is a condition wherein there is a deficiency of red blood cells. The red cells assist with carrying oxygen all through the body. Too few red cells can deny the tissues of oxygen, causing side effects like exhaustion, fatigue, and shortness of breath.
-
Thrombocytopenia: It is a condition characterized by a decrease in the number of platelets. Platelets are responsible for the coagulation of blood when one is hurt or while bleeding. A low platelet count might cause a greater risk of bleeding and bruising.
-
Splenomegaly: It is a condition that causes swelling of the spleen. The spleen is responsible for the number of blood cells that are produced. An excessive number of unusual platelets can cause the spleen to swell in size. The swelling of the spleen can be felt as a discomfort in the upper abdomen.
-
Extramedullary Hematopoiesis: Strange development of premature blood cells outside the bone marrow. These cells can travel to other body organs, such as the kidney, heart, lungs, and liver. These cells can prevent the normal functioning of the cells as they form tumor-like growth.
-
Portal Hypertension: An increase in the blood pressure in the vein that carries the blood to other organs such as the liver or spleen.
In around 12 % of all cases, essential myelofibrosis advances to intense myeloid leukemia, an exceptionally forceful type of blood malignant growth.
What Are the Symptoms of Primary Myelofibrosis?
Primary myelofibrosis has a very slow progression. Many of the patients do not have any symptoms for many years. Early symptoms for this condition are very rare. The most common symptoms of this condition include:
-
Fatigue
-
Fever.
-
Weight loss.
-
Night sweating.
-
Pale skin.
-
Enlarged liver or spleen.
-
Recurrent infections.
-
Bruising of the skin.
-
Enlargement of the veins of the liver and spleen.
-
Pain in the bones and joints.
How Is Primary Myelofibrosis Diagnosed?
The doctor (oncologist) will carry out various tests and get information about one’s clinical history, including any side effects the person may encounter. The doctor will check for indications of an enlarged spleen and anemia. They will perform different tests to preclude different circumstances and confirm the diagnosis. The various tests may include-
1. Blood Tests:
-
Complete Blood Count (CBC): This test estimates the number of platelets. A lower than ordinary number of red blood cells and increased measures of white blood cells and platelets can suggest myelofibrosis.
-
Peripheral Blood Smear (PBS): This test may show that the platelets are unusual in size, shape, or different elements. Strange-looking cells and a large number of premature platelets might be an indication of myelofibrosis.
-
Blood Chemistry Analysis: These tests measure levels of different substances the organs discharge into the blood. They can show how an organ works. Elevated degrees of bilirubin and lactic dehydrogenase may flag myelofibrosis.
2. Bone Marrow Tests:
-
Bone Marrow Biopsy: This test uses a sample of bone marrow that will be visualized under the microscope to check for any abnormalities. The morphology of the cells will help to diagnose myelofibrosis.
-
Bone Marrow Aspiration: This test uses the liquid component of the bone marrow so the physician can inspect it for indications of myelofibrosis.
How Is Myelofibrosis Treated?
One does not require treatment until symptoms appear. In any case, the doctor will monitor the condition regularly to look for symptoms. The various drugs used in the treatment of primary myelofibrosis include- Ruxolitinib, Fedratinib, and Pacritinib. These are United States Food and Drug Administration (FDA)- endorsed drugs for treating moderate or high-risk myelofibrosis. Each of the three medications is a JAK inhibitor that decreases overactive Janus-related kinase (JAK) flagging. They assist with letting some free from the side effects related to myelofibrosis, including an enlarged spleen, night sweats, tingling, weight reduction, and fever.
For the vast majority, treatment objectives are to oversee conditions related to myelofibrosis, including iron deficiency and splenomegaly.
Conclusion
Primary myelofibrosis is a condition of the blood system in which a scar or fibrous tissue forms within the bone marrow space. This condition is asymptomatic in the early stages of the condition. When detected at the early stages, this condition can be managed in a better way.
