Table 1 Bone marrow fibrosis grading systems for the quantification of bone marrow reticulin and collagen
From: Fibrosis and bone marrow: understanding causation and pathobiology
0 | No demonstrable reticulin fibres |
1 | Occasional fine individual fibres and focal fine fibre network |
2 | Fine fibre network throughout most of the section; no coarse fibres |
3 | Diffuse fibre network with scattered thick coarse fibres but no mature collagen (negative trichrome staining) |
4 | Diffuse, often coarse fibre network with areas of collagenization (positive trichrome staining) |
II. European consensus on the grading of bone marrow fibrosis*[4] | |
|---|---|
MF-0 | Scattered linear reticulin with no intersection (cross-overs) corresponding to normal bone marrow |
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 only focal bundles of collagen and/or focal osteosclerosis |
MF-3 | Diffuse and dense increase in reticulin with extensive intersections with coarse bundles of collagen, often associated with significant osteosclerosis |