Grading of myelofibrosis
| Myelofibrosis grading . | |
|---|---|
| MF-0 | Scattered linear reticulin with no intersections (crossovers) corresponding to normal BM |
| MF-1 | Loose network of reticulin with many intersections, especially in perivascular areas |
| MF-2 | Diffuse and dense increase in reticulin with extensive intersections, occasionally with focal bundles of thick fibers mostly consistent with collagen, and/or focal osteosclerosis* |
| MF-3 | Diffuse and dense increase in reticulin with extensive intersections and coarse bundles of thick fibers consistent with collagen, usually associated with osteosclerosis* |
| Myelofibrosis grading . | |
|---|---|
| MF-0 | Scattered linear reticulin with no intersections (crossovers) corresponding to normal BM |
| MF-1 | Loose network of reticulin with many intersections, especially in perivascular areas |
| MF-2 | Diffuse and dense increase in reticulin with extensive intersections, occasionally with focal bundles of thick fibers mostly consistent with collagen, and/or focal osteosclerosis* |
| MF-3 | Diffuse and dense increase in reticulin with extensive intersections and coarse bundles of thick fibers consistent with collagen, usually associated with osteosclerosis* |
Semiquantitative grading of BM fibrosis (MF) with minor modifications concerning collagen and osteosclerosis. Fiber density should be assessed only in hematopoietic areas.
In grades MF-2 or MF-3 an additional trichrome stain is recommended.