Algorithm for Bone Marrow Examination

· Clinical History

· Indication

· Meds / Chemo / Growth Factors

· Peripheral Blood:

· Automated differential

· Algorithm for peripheral blood examination

· Aspirate:

· Adequacy (10x objective)

· Number and cellularity of particles (squash is best for cellularity)

· Number of megakaryocytes (squash is best)

· Dilute: absence of particles but presence of megakaryocytes or other precursor cells

· (Hypocellular, Inadequate for interpretation precluding a differential)

· Number of smears, number of touch preps

· Scan for clumps of abnormal cells or scattered abnormal cells (10x) (squash is best for focal lesions including lymphoma, plasma cell myeloma, mast cells, metastatic carcinoma, storage histiocytes, granulomas)

· Parasites

· Cell inclusions

· Differential (smears are best) (at least 500 cells in at least 2 smears if a precise percentage of abnormal cell type is required; otherwise at least 300 cells)

· # of cells counted

· Blasts

· Promyelocytes

· Myelocytes

· Metamyelocytes

· Bands

· PMNs

· Eos Myelo/Meta

· Eos Band

· Eos Seg

· Basophils

· Mast cells

· Promonocytes

· Monocytes

· Pronormoblasts

· Normoblasts

· Lymphocytes

· Plasma cells

· Other

· Don’t include:

· Megakaryocytes

· Macrophages

· Osteoblasts

· Osteoclasts

· Stromal cells

· Smudged cells

· Non-haemopoietic cells

· Lymphoid aggregates

· Myeloid:Erythroid (normal 1.5 – 3.3)

· Myeloid includes all granulocytes and monocytes and their precursors

· Erythroid includes all stages of differentiation

· Cellularity (squash prep is best)

· (mildly, moderately, markedly)

· (increased, decreased, unremarkable, not evaluable)

· Erythroid maturation

· (complete, slight, moderate, marked, megaloblastoid, megaloblastic, asynchronous)

· dyserythropoietic forms

· Myeloid maturation

· (complete, slight, moderate, marked)

· megaloblastoid, megaloblastic

· with a left shift

· with dysplastic forms

· with pseudo-Pelger-Huet forms

· Megakaryocytes:

· (present in, absent)

· (mildly, moderately, markedly)

· (increased, decreased, normal) numbers

· with clusters, aggregates, very large aggregates present

· monolobate

· hypersegmented

· small

· non-budding

· dysplastic forms

· Biopsy:

· Adequacy

· Fragmented

· Crushed

· Inadequate for interpretation

· Hemorrhagic

· Contains a large amount of cartilage, cortical bone, periosteum

· Clot section / particle preparation:

· Adequacy

· Fragmented

· Crushed

· Inadequate for interpretation

· Stainable iron (smear is best; less reliable on decalcified specimen):

· (absent, decreased, normal, increased, markedly increased)

· ringed sideroblasts

· (no, rare, moderate numbers of, numerous) (at least 100 erythroblasts should be evaluated for the percentage of ring sideroblasts, if present)

· definition: 5 or more siderotic granules encircling one third or more of the nucleus

· location (cytoplasmic or perinuclear) of siderotic granules

· Focal lesions

· Bony trabeculae

· (unremarkable, thinned, show osteoclastic resorption, osteoblastic rimming, show new bone formation)

· Cytochemical stains

· Immunohistochemical stains

· in situ hybridization

· Comparison to previous BM sample

References:

· Steven H. Swerdlow. University of Pittsburgh School of Medicine Department of Pathology. Hematopathology handbook for residents and fellows.

· Lee S-H, Erber WN, Porwit A, Tomonaga M, Peterson LC for the International Council for Standardization in Hematology. ICSH guidelines for the standardization of bone marrow specimens and reports. Int J Lab Hem 2008;30:349-364.