Myelofibrosis is also known as primary myelofibrosis (PMF), is a rare bone marrow disorder which is classified under myeloproliferative neoplasms. A mutation in the hematopoietic stem cell leads to abnormal cell formation and scar tissue formation which leads to reduced normal blood cell production and scarring of the bone marrow. Most patients are asymptomatic for years and symptoms occur when the blood cells are significantly low to carry on with the normal body functions. The prevalence of myelofibrosis is 1 in 100,000 persons and it’s common in the elderly population (60-70 years).
What Is The Prognosis For Myelofibrosis?
There are many prognostic scoring systems but two of the most commonly used prognostic scoring systems are:
International Prognostic Scoring System (IPSS) developed in 2009 by the International Working Group for Myelofibrosis Research and Treatment (IWG-MRT). IPSS is based on the risk factors present at the time of diagnosis and it is more suitable for newly diagnosed patients. The 5 adverse prognostic factors with the number of points are:
- Age >65 years – 1 point
- Hemoglobin <10 g/dl – 1 point
- Constitutional symptoms – 1 point
- Leukocyte count >25 × 109/l – 1 point
- Circulating blasts ≥1% – 1 point
Later IPSS was validated and dynamic IPSS (DIPSS) was developed by IWG-MRT in 2010. DIPSS has taken into account the progression of the disease with time and it can be used at any time of the clinical course of the disease. This is also useful in predicting the progression to blast phase (leukemic stage) and the outcome after allogeneic stem cell transplantation. The same 5 adverse prognostic factors are used but the points allocation is different
- Age >65 years – 1 point
- Hemoglobin <10 g/dl – 2 points
- Constitutional symptoms – 1 point (fatigue, fever, night sweats, loss of weight)
- Leukocyte count >25 × 109/l – 1 point
- Circulating blasts ≥1% – 1 point
Based on the number of adverse prognostic factors patients are categorized into 4 groups and for each group the years of median survival rate is given.
IPSS
Risk category | Number of risk factors | Median survival (years) |
Low | 0 | 11.3 |
Intermediate -1 | 1 | 7.9 |
Intermediate -2 | 2 | 4.0 |
High | ≥3 | 2.3 |
DIPSS
Risk category | Number of risk factors | Median survival (years) |
Low | 0 | Not reached |
Intermediate -1 | 1-2 | 14.2 |
Intermediate -2 | 3-4 | 4 |
High | 5-6 | 1.5 |
There is no cure for myelofibrosis but symptoms can be controlled with treatment so, that the patient can be symptoms-free for some period. The natural course of myelofibrosis is highly variable among individual patients, some patients live long periods a normal or near normal life and they might not need much treatment. Whereas, for some people, myelofibrosis progress rapidly and they need robust treatment to control the symptoms. Other than the prognostic factors mentioned-above hepatosplenomegaly, platelet disorders (increased or decreased platelets), thrombosis, bleeding and gout are some symptoms with a poor prognosis. The risk of developing acute leukemia (mainly acute myeloid leukemia) is 8-23% within the first 10 years after diagnosis.(1)
Cause Of Death In Myelofibrosis
- Transformation to acute leukemia – most common cause
- Primary myelofibrosis progression without transformation
- Thrombosis and heart complications
- Infections
- Bleeding
- Portal hypertension
- Transplant complications
- Secondary neoplasms
Conclusion
Myelofibrosis is a rare bone marrow disease which occurs in 1 out of 100,000 persons classified under myeloproliferative neoplasms. The most commonly used prognostic scoring systems are the IPSS and DIPSS developed by IWG-MRT. IPSS is based on the risk factors present at the time of diagnosis and it is more suitable for newly diagnosed patients whereas, DIPSS has taken into account the progression of the disease with time and it can be used at any time of the clinical course of the disease. Five adverse prognostic factors are considered and a score is given, according to that score 4 categories are classified as low, intermediate-1, intermediate-2 and high. The highest category in IPSS has a median survival rate of 2.3 years and in the DIPSS it’s 1.5 years. There is no cure for myelofibrosis and the clinical course is highly variable. From myelofibrosis patients 8-23% patients develop acute leukemia within the first 10 years after diagnosis.
Also Read:
- Can A Bone Marrow Transplant Cure Myelofibrosis?
- How To Prevent Myelofibrosis?
- What Is Post Polycythemia Vera Myelofibrosis?
- Home Remedies For Myelofibrosis
- What Are The Different Types Of Myelofibrosis?
- Who Is At Risk For Myelofibrosis & What Are The Complications?
- Alternative Treatment For Myelofibrosis