Plastic embedded core biopsy: a complementary approach to bone marrow aspiration for diagnosing acute myeloid leukaemia

To evaluate the role of bone marrow aspiration and bone marrow biopsy in pancytopenia

BACKGROUND

Pancytopenia is not a disease entity but a triad of findings that may result from various disease processes, primarily or secondarily involving the bone marrow. Bone marrow aspiration and biopsy evaluation along with good clinical correlation is of utmost importance to evaluate the causes of pancytopenia and planning further investigations.

AIMS

The present study was a prospective clinicohaematological study undertaken to analyse the various causes of pancytopenia by evaluating bone marrow aspiration and biopsy and correlating with clinical findings, complete blood counts and peripheral blood picture.

MATERIALS AND METHODS

Fifty patients of pancytopenia were included in the study in which relevant history and physical examination findings were recorded. Bone marrow aspiration and biopsy were performed simultaneously in all cases. Perl's stain was done in all cases and special stains like MPO, PAS and reticulin were also done wherever necessary.

RESULTS AND CONCLUSION

The maximum cases of pancytopenia were in the age group of 10 to 30 y with male preponderance. Aplastic anaemia was found to be the most common aetiology of pancytopenia followed by normoblastic erythroid hyperplasia, megaloblastic anaemia, acute leukemias, myelofibrosis, lymphoid neoplasia and iron deficiency anaemia. It was concluded from the study that although the advantages of bone marrow aspiration and biopsy differ, both are complimentary to each other and should be performed simultaneously for a complete bone marrow work up and evaluation. It is only through the correlation of clinical, hematological and bone marrow examination findings that proper evaluation and management of patients of pancytopenia can be made.

Bone marrow cellularity in myeloid stem cell disorders: impact of age correction

We have reviewed the initial diagnostic bone marrow aspirate and biopsy specimens performed on the same date on 92 patients with acute myeloid leukaemia (AML), 100 patients with myelodysplastic syndrome (MDS), 24 patients with chronic granulocytic leukaemia (CGL), 19 patients with polycythemia vera (PV) and essential thrombocythemia (ET). An excellent assessment of cellularity by aspirate and biopsy was found. The estimation of BM cellularity for each group was utilized with and without age adjustment based on normal marrow biopsies. Without correcting the BM cellularity for age it was observed that the median BM cellularity was > 50% in AML, CGL, PV and ET. In contrast, the median BM cellularity was estimated at 40% for MDS. In the age group 70 years and beyond the median BM cellularity was not changed in CGL, PV and ET, and only slightly decreased (35%) in MDS. However, a trend from hypercellularity to normocellularity was observed in patients with AML in this age group. By utilizing anatomic comparisons with normal age the corrected data disclosed that all patients with CGL, PV and ET, 63% of patients with AML and only 35% of patients with MDS had hypercellular BM according to their age, while only two patients with AML and seven patients with MDS were found to be truly hypocellular by age. The optimal cut-off value for definition of hypocellular AML and hypocellular MDS, and differences between MDS and other myeloid stem cell disorders in terms of BM cellularity have been discussed.

Proposal for a classification of acute myeloid leukaemia based on plastic-embedded bone marrow biopsy sections

Traditional approaches to haematological diagnosis of acute myeloid leukaemia (AML) include microscopic examination of peripheral blood (PB) and bone marrow (BM) cells studied in Romanowsky-stained, dry film smears. The routine evaluation of BM aspirates, however, may be disappointing in accurately assessing marrow activity because of the sampling error inherent in the BM aspiration technique, and occasionally may fail to provide a precise diagnosis because BM aspirates cannot be obtained due to packed or fibrotic marrows. Because of the advantages it offers over the conventional method of diagnosis, we have studied Romanowsky-stained, thin sections of plastic-embedded BM biopsies from 87 newly diagnosed AML patients. Based on our study, the patients were broadly grouped into four categories: (1) those with hypocellular marrow (haemopoietic cellularity less than 50%), hypoplastic AML; (2) those with some degree of marrow fibrosis, AML with marrow fibrosis; (3) those with homogeneous infiltration of marrow with blast cells; and (4) those with inhomogenous infiltration of marrow with blast cells. Our results show that the proposed classification of AML based on the evaluation of plastic-embedded BM biopsy sections may offer benefits over those afforded by conventional morphologic smear techniques. This may provide significant prognostic information and may have a major impact on patient management. It may also provide a meaningful stratification of the patient population when comparing treatment protocols for newly diagnosed AML patients.

Bone marrow histology. 3: Value of bone marrow core biopsy in acute leukaemia, myelodysplastic syndromes, and chronic myeloid leukaemia

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