Overview

Myelofibrosis is a serious bone marrow disorder that disrupts your body's normal production of blood cells. The result is extensive scarring in your bone marrow, leading to severe anemia, weakness, fatigue and often an enlarged spleen.

Myelofibrosis is an uncommon type of chronic leukemia — a cancer that affects the blood-forming tissues in the body. Myelofibrosis belongs to a group of diseases called myeloproliferative disorders.

Many people with myelofibrosis get progressively worse, and some may eventually develop a more serious form of leukemia. Yet it's also possible to have myelofibrosis and live symptom-free for years. Treatment for myelofibrosis, which focuses on relieving symptoms, can involve a variety of options.

Source: http://www.mayoclinic.com

Symptoms

Myelofibrosis usually develops slowly. In its very early stages, many people don't experience signs or symptoms.

As disruption of normal blood cell production increases, signs and symptoms may include:

• Feeling tired, weak or short of breath, usually because of anemia
• Pain or fullness below your ribs on the left side, due to an enlarged spleen
• Easy bruising
• Easy bleeding
• Excessive sweating during sleep (night sweats)
• Fever
• Bone pain

When to see a doctor

Make an appointment with your doctor if you have any persistent signs and symptoms that worry you.

Source: http://www.mayoclinic.com

Causes

Myelofibrosis occurs when blood stem cells develop a genetic mutation. Blood stem cells have the ability to replicate and divide into the multiple specialized cells that make up your blood — red blood cells, white blood cells and platelets.

It's not clear what causes the genetic mutation in blood stem cells.

As the mutated blood stem cells replicate and divide, they pass along the mutation to the new cells. As more and more of these mutated cells are created, they begin to have serious effects on blood production.

The end result is usually a lack of red blood cells — which causes the anemia characteristic of myelofibrosis — and an overabundance of white blood cells with varying levels of platelets. In people with myelofibrosis, the normally spongy bone marrow becomes scarred.

Several specific gene mutations have been identified in people with myelofibrosis. The most common is the Janus kinase 2 (JAK2) gene. Knowing whether the JAK2 gene or others are associated with your myelofibrosis helps determine your prognosis and your treatment.

Source: http://www.mayoclinic.com

Diagnosis

Tests and procedures used to diagnose myelofibrosis include:

• Physical exam. Your doctor will perform a physical exam. This includes a check of vital signs, such as pulse and blood pressure, as well as checks of your lymph nodes, spleen and abdomen.
• Blood tests. In myelofibrosis, a complete blood count typically shows abnormally low levels of red blood cells, a sign of anemia common in people with myelofibrosis. White blood cell and platelet counts are usually abnormal, too. Often, white blood cell levels are higher than normal, although in some people they may be normal or even lower than normal. Platelet counts may be higher or lower than normal.
• Imaging tests. Imaging tests, such as X-rays and magnetic resonance imaging (MRI), may be used to gather more information about your myelofibrosis.

• Bone marrow examination. Bone marrow biopsy and aspiration can confirm a diagnosis of myelofibrosis.

  In a bone marrow biopsy, a needle is used to draw a sample of hardened bone marrow from your hipbone. During the same procedure, another type of needle may be used to withdraw a sample of the liquid portion of your bone marrow. The samples are studied in a laboratory to determine the numbers and types of cells found.

• Gene tests. A sample of your blood or bone marrow may be analyzed in a laboratory to look for gene mutations in your blood cells that are associated with myelofibrosis.

Source: http://www.mayoclinic.com

Complications

Complications that may result from myelofibrosis include:

• Increased pressure on blood flowing into your liver. Normally, blood flow from the spleen enters your liver through a large blood vessel called the portal vein. Increased blood flow from an enlarged spleen can lead to high blood pressure in the portal vein (portal hypertension). This in turn can force excess blood into smaller veins in your stomach and esophagus, potentially causing these veins to rupture and bleed.
• Pain. A severely enlarged spleen can cause abdominal pain and back pain.
• Growths in other areas of your body. Formation of blood cells outside the bone marrow (extramedullary hematopoiesis) may create clumps (tumors) of developing blood cells in other areas of your body. These tumors may cause problems such as bleeding in your gastrointestinal system, coughing or spitting up of blood, compression of your spinal cord, or seizures.
• Bleeding complications. As the disease progresses, your platelet count tends to drop below normal (thrombocytopenia) and platelet function becomes impaired. An insufficient number of platelets can lead to easy bleeding — an issue that you and your doctor will want to discuss if you're contemplating any type of surgical procedure.
• Painful bones and joints. Myelofibrosis can lead to hardening of your bone marrow and inflammation of the connective tissue that is found around the bones. This may cause bone and joint pain.
• Acute leukemia. Some people with myelofibrosis eventually develop acute myelogenous leukemia, a type of blood and bone marrow cancer that progresses rapidly.

Coping and support

Living with myelofibrosis may involve coping with pain, discomfort, uncertainty and the side effects of long-term treatments. The following steps may help ease the challenge and make you feel more comfortable and in charge of your health:

• Learn about your condition. Myelofibrosis is fairly uncommon. To help you find accurate and trustworthy information, ask your doctor to direct you toward appropriate sources. Based on these sources, find out as much as you can about myelofibrosis.

• Get support. Take this opportunity to lean on family and friends. It can be tough to talk about your diagnosis, and you'll likely get a range of reactions when you share the news. But talking about your diagnosis and passing along information about your condition can help. So can the offers of help that often result.

  You may also benefit from joining a support group, either in your community or on the internet. A support group of people with the same or a similar diagnosis, such as a myeloproliferative disorder or another rare disease, can be a source of useful information, practical tips and encouragement.

• Explore ways to cope with the disease. If you have myelofibrosis, you may face frequent blood work and medical appointments and regular bone marrow exams. Some days, you may feel sick even if you don't look sick. And some days, you may just be sick of being sick.

  Try to find some activities that help, whether it's yoga, exercise, social outings or adopting a more flexible work schedule. Talk to a counselor, therapist or oncology social worker if you need help dealing with the emotional challenges of this disease.

Source: http://www.mayoclinic.com

Risk factors

Although the cause of myelofibrosis often isn't known, certain factors are known to increase your risk:

• Age. Myelofibrosis can affect anyone, but it's most often diagnosed in people older than 50.
• Another blood cell disorder. A small portion of people with myelofibrosis develop the condition as a complication of essential thrombocythemia or polycythemia vera.
• Exposure to certain chemicals. Myelofibrosis has been linked to exposure to industrial chemicals such as toluene and benzene.
• Exposure to radiation. People exposed to high levels of radiation, such as survivors of atomic bomb attacks, have an increased risk of myelofibrosis. Some people who received a radioactive contrast material called Thorotrast, used until the 1950s, have developed myelofibrosis.

Source: http://www.mayoclinic.com