BONE MARROW ASPIRATE AND BIOPSY

When they are indicated, how they are collected and processed in histology, why a final report/interpretation may take a little longer to obtain than other surgical pathology specimens (decal, special stains, etc.), and what general areas are evaluated in a bone marrow by a pathologist.

I. INDICATIONS

1. Investigation of peripheral blood abnormality-unexplained cytopenia.

2. Suspected marrow replacement (myelofibrosis, metastatic malignency, or storage disease).

3. Suspected leukemia or primary malignancy of marrow.

4. Unexplained lymphadenopathy, splenomegaly, or hepatomegaly.

5. Staging of Hodgkin disease or non-Hodgkin lymphoma.

6. Evaluation for fever of unknown origin.

7. Evaluation of marrow iron store.

8. Ongoing monitoring of patients with variety of hematologic and lymphoreticular disorders.

9. Bone marrow examination is virtually required for all pancytopanic patients, except those receiving bone marrow suppressive therapy.

II. CONTRAINDICATIONS

1. Hemophilia.

2. Thrombocytopenia - is not.

3. Radiation or skin infection at the side of aspiration.

III. COMPLICATIONS

1. Bleeding

2. Local Infection

3. Neusopathy

4. Fracture

IV. COLLECTION AND PROCESSING OF SPECIMENS

1. BM aspirate

- 0.5-2.0 ml

- aspirate in EDTA

- clotted aspirate in B5

2. BM biopsy

- 1.0-2.0 cm

- touch preparation (before fixation)

- in B5 fixative

3. Additional aspirate in ACD (acid citrate dextrose)

- flow cytometry

- chromosome analysis

- molecular study

V. TYPES OF PREPARATIONS

1. BM aspirate

- smear

2. Clot section

3. BM biopsy

- touch preparation (imprint smear)

- section

VI. ROUTINE STAINS

1. H&E (S)

2. Iron (F, S) - Prussian blue

3. Reticulin (S)

4. Trichrome (S)

5. Wright-Gimsa (F)

VII. SPECIAL STAINS

1. Tartrate-resistant acid phosphatase (+) HCL.

2. Myeloperoxidase and Sudan blackmarkers for granulocytic lineage (+) AML.

3. Naphtyl acetate esterase-enzyme in monocytes/macrophage. Monocytic v/s Granulocytic leukemia.

4. Immunostains

- CD20-Bcelss.

- CD45RO-Tcells.

- CD15 (LeuM1) -Hodgkin disease.

- Cytokeratin - Carcinoma.

VIII. EXAMINATION OF BONE MARROW

1. Peripheral blood-CBC, including platelet and retic. count.

2. Bone marrow cellularity

- smear.

- bx section (best determined).

3. Differential cell count

- distribution.

- maturation.

- M:E ratio 1.2:1 to 4:1.

- number of megakaryocytes 1 to 3 in each field (100x).

4. Evaluation of stroma, vessels, bone (bx section).

5. Detection of lymphoma, granuloma, metastatic tumor, vasculitis (bx section).

6. Special stain and studies.

IX. BONE MARROW REPORT

1. Peripheral blood & CBC.

2. BM aspirate.

3. BM touch preparation.

4. BM biopsy.

5. Clot section.

6. Special studies.

The diagnosis is estimated based on findings in peripheral blood bone marrow and clinical history.