From the Guidelines
Secondary myelofibrosis, also known as bone marrow fibrosis, is a condition where there is scarring in the bone marrow due to a secondary cause, such as infection, autoimmune disorder, or other chronic inflammatory condition, rather than a primary myeloproliferative neoplasm.
Key Characteristics
- Secondary myelofibrosis is not a primary myeloproliferative neoplasm, but rather a reactive process to an underlying condition 1
- It can be caused by various factors, including infection, autoimmune disorders, hairy cell leukemia, lymphoid neoplasms, metastatic malignancies, or toxic myelopathies 2, 1
- The diagnosis of secondary myelofibrosis requires the exclusion of primary myelofibrosis and other myeloproliferative neoplasms, such as polycythemia vera and essential thrombocythemia 3 ### Diagnostic Considerations
- A bone marrow biopsy is essential for the diagnosis of secondary myelofibrosis, as it can help identify the underlying cause of the fibrosis 2
- The presence of megakaryocyte proliferation and atypia, reticulin or collagen fibrosis, and increased bone marrow cellularity can be seen in both primary and secondary myelofibrosis, making it essential to exclude primary myeloproliferative neoplasms 1
- The demonstration of a clonal marker, such as JAK2 V617F, can help distinguish primary myelofibrosis from secondary myelofibrosis 2, 1
From the Research
Definition and Characteristics of Secondary Myelofibrosis
- Secondary myelofibrosis, also known as bone marrow fibrosis, is a condition characterized by the deposition of collagen, fibronectin, and laminin in the bone marrow 4.
- It can be either a primary or secondary disorder, with secondary myelofibrosis usually responding to appropriate treatment of the underlying disease 4.
- Bone marrow fibrosis is a histologic finding in a wide range of diseases, including malignancies, endocrine disorders, autoimmune diseases, and infections 5.
Causes and Associations of Secondary Myelofibrosis
- Secondary bone marrow fibrosis is associated with many disease conditions, including oncologic diseases, hematologic diseases, and miscellaneous diagnoses 6.
- An underlying oncologic disease is more frequently associated with marked fibrosis compared to hematologic and miscellaneous diagnoses 6.
- Autoimmune myelofibrosis (AIMF) is a rare cause of bone marrow fibrosis, occurring in the presence or absence of a defined autoimmune disease 7.
Treatment and Outcome of Secondary Myelofibrosis
- Secondary myelofibrosis usually responds to appropriate treatment of the underlying disease 4.
- The outcome of secondary bone marrow fibrosis ranges from worsening of fibrosis to complete resolution, with a majority of patients showing complete resolution of fibrosis after treatment 6.
- Immunotherapy is an effective treatment for autoimmune myelofibrosis, with most cases responding well to immunosuppressive therapy 7.