From the Guidelines
Reticulin and trichrome stains are the primary stains used to assess bone marrow fibrosis, with reticulin stain highlighting reticulin fibers and trichrome stain identifying advanced collagen fibrosis, and both should be performed for a complete evaluation, as recommended by the most recent guidelines 1. When evaluating bone marrow fibrosis, pathologists typically grade it on a scale from MF-0 (no fibrosis) to MF-3 (severe fibrosis) according to the European consensus system.
- The presence and degree of fibrosis provide important diagnostic and prognostic information for conditions like primary myelofibrosis, other myeloproliferative neoplasms, and metastatic malignancies.
- Reticulin stain (silver impregnation technique) is most commonly used to detect early fibrosis by highlighting reticulin fibers.
- Trichrome stain (such as Masson's trichrome) identifies more advanced collagen fibrosis.
- These stains are essential because fibrosis is not adequately visualized with routine hematoxylin and eosin (H&E) staining.
- In grades MF-2 or MF-3, an additional trichrome stain is recommended, as stated in the guidelines 1.
- The use of reticulin and trichrome stains is also supported by other studies, such as those on myelodysplastic syndromes 1, which highlight the importance of evaluating bone marrow fibrosis in these conditions.
From the Research
Staining for Bone Marrow Biopsy Fibrosis
- The most commonly used stain for detecting fibrosis in bone marrow biopsies is the Gömöri silver impregnation method 2.
- This method is used to evaluate the grade and extent of myelofibrosis (MF) in bone marrow biopsies, which is essential for the diagnosis and prognosis of myeloproliferative disorders 2.
- Other stains, such as trichrome stains, can also be used to detect collagen fibrosis in bone marrow biopsies, which is often associated with more severe disease and a poorer prognosis 3.
Detection of Reticulin Fibers
- Reticulin fibers can be detected using silver staining of tissue sections, which is a common method for evaluating bone marrow reticulin fibrosis (RF) 4.
- The degree of reticulin fibrosis can be graded using a scoring system, such as the European Consensus on Grading of Bone Marrow Fibrosis (ECGMF) grade 5.
- Advanced reticulin fibrosis has been associated with poor prognosis and increased mortality in patients with primary myelofibrosis (PMF) and chronic lymphocytic leukemia (CLL) 5, 6.
Clinical Significance
- The detection of bone marrow fibrosis has important clinical implications, as it can affect the diagnosis, prognosis, and treatment of various hematological disorders 2, 3, 5, 6.
- A comprehensive histological evaluation of reticulin fibrosis, collagen deposition, and osteosclerosis in bone marrow biopsies can provide valuable prognostic information for patients with PMF 5.
- The presence of advanced reticulin fibrosis at diagnosis has been associated with poor survival and increased mortality in patients with CLL 6.