Bone Marrow
A comprehensive bone marrow examination generally includes aspirate smears, a biopsy core, clot sections, and touch imprints prepared from the biopsy. Standard inclusion of all components varies widely between institutions, due to varying opinions regarding the diagnostic utility of the different components in various clinical situations. This variability could conceivably have an impact on diagnostic accuracy and turnaround time.
A retrospective study investigated the diagnostic utility of the different bone marrow components, by reviewing 4,902 bone marrow samples obtained over a ten year period at a tertiary medical center (Am. J. Hematol. 56:37-41, 1997). In this series, two thirds of patients undergoing bone marrow examination did so for staging of malignancy (carcinoma or lymphoma), follow-up for acute leukemia, or evaluation of cytopenias.
The study found that both aspirate and biopsy are necessary for complete evaluation in staging of carcinoma and lymphoma. As many as 25% of bone marrows positive for small cell lung carcinoma and 32% of bone marrows positive for all carcinomas would have been missed on aspirate alone. Similarly, in non-Hodgkin’s lymphomas (NHL), aspirates were diagnostic of marrow involvement in only 38% of cases (see Table). In Hodgkin’s lymphoma, all 15 cases with marrow involvement were detected only on the biopsy. The authors also confirm that bilateral biopsies are indicated for both carcinoma and lymphoma staging, since 32% of positive carcinoma cases and 23% of positive lymphoma cases were positive on one side only. One advantage of aspirates and touch preparations in carcinoma staging is their earlier availability, which allowed diagnosis of bone marrow involvement one day sooner in 85% of carcinomas. Finally, the clot section has definite, although limited value, since 1-2% of all positive carcinoma and lymphoma cases were detected only in this component.
Diagnostic Value Of Different Bone Marrow Components
|
Disease |
Dx on aspirate(%) |
Dx on biopsy imprint (%) |
Positive only on biopsy (%) |
Positive only on clot (%) |
|
Carcinoma |
68 |
17 |
14 |
1 |
|
NonHodgkins Lymphoma |
38 |
5 |
56 |
1 |
|
Hodgkin’s Lymphoma |
0 |
- |
100 |
- |
|
Acute leukemia |
88 |
2 |
10 |
- |
|
Cytopenias |
92 |
- |
8 |
- |
The authors recommended that unilateral aspirate and biopsy are indicated for evaluation following treatment for acute leukemia and in the evaluation of cytopenias. The aspirate was diagnostic of involvement in 88% of acute leukemia cases, while a further 10% of cases was positive in the biopsy alone. In cases presenting with cytopenias, an aspirate was diagnostic in 92% of cases while a biopsy was required for diagnosis in the remaining 8%.In conclusion, this study illustrates how submission of appropriate bone marrow samples has a major impact on accurate and timely disease staging and diagnosis
