Clinical context

Elderly patient with macrocytic anaemia and thrombocytopenia

At a glance

Stain	MGG

About Myelodysplasia with Monosomy 7

This bone marrow is from a patient with MDS / Monosomy 7. Monosomy 7 is a common finding in myeloid malignancies, including MDS. Note this is acquired monosomy 7 - congenital/inherited monosomy 7 causes its own spectrum of disease which does include bone marrow failure.

Within the bone marrow, one key is that despite cytopenias in the peripheral blood, the bone marrow particles are hypercellular. There are a mix of normal and abnormal cells. Some megakaryoctes are normal, whereas others are abnormal, with hyplobation and disparate nuclei.

Following the normal bone marrow reporting schema - red cells are reduced, but all stages are seen from erythoblast through to normoblast. There are many cells with ragged nuclei and some nuclear cytoplasmic dys-synchrony. The myeloid series shows all stages of maturation. There is no excess of blasts or promyelocytes. Myelocytes are numerous. Mature neutrophils are hypogranular and reduced in number.

Overall, the bone marrow shows signs of trilineage dysplasia. Correlation with clinical indices, molecular, cytogenetics, flow cytometry and histopathology recommended.

Morphological features

Particle

This particls is well stained and hypercellular given that the patient is elderly.

Megakaryocyte

Megas in this marrow are reduced, hypolobated, with disparate and displaced nuclei. These are consistent with MDS, rather than specifically for Monosomy 7

Basophillic erythroblast

This is a tough one - it's an immature cell, but probably it's an abnormal erythroid precursor which we wouldn't normally see. It's not a myeloid blast. Blasts are also not particularly high in this marrow - 1 or 2 percent only.

Myelocyte

This is a myelocyte. The cell has started to mature, and is clearly a myeloid cell. There are granules, the nucleus has started to condense and it has lost it's prominent golgi which would make it a promyelocyte. Remember that blast to promyelocyte to myelocyte doesn't happen inbstantly - it's a continuous evolution and some cells will overlap features as they differentiate.

Normal Megakaryocyte

One of the rarer normal megakaryocytes in this marrow. The others are hypolobated or have abnormal nuclear structure. This one looks pretty healthy.

Promyelocyte

This cell is a promyelocyte, with a nucleus that has started differentiation and has acquired granules. The key which makes this a pro- not just a myelocyte is the prominent golgi zone - the pale circle indenting in the nucleus. This is a feature of promyelocytes and really helps with differentiation.

Hypogranular Neutrophils

These neutrophils look extremely hypogranular - this is a feature of myelodysplasia

Myeloid Blast

This cell has a high NC ratio, open chromatin, no golgi zone and clear granules. It's a blast.

Ragged Nucleus

This normoblast has an irregularly shaped nucleus - it's not circular with a uniform density. This is called having a regged nucleus, and is a feature of MDS

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