CD34 immunohistochemistry in bone marrow biopsies for early response assessment in acute myeloid leukemia

Abstract

Introduction: Acute myeloid leukemia is a heterogenous disease with respect to prognosis. Early response assessment has an established role as predictor of remission rate, and overall and disease-free survival. Assessment of blast percentage on bone marrow aspirate smears at this stage has its own limitations.

Materials and method: In this study, a total of 100 AML cases that were positive for CD34 at the time of diagnosis were included in the study. Blast percentage obtained in bone marrow aspirate smears by morphology was compared with that obtained in bone marrow biopsy using CD34 immunohistochemistry.

Results: Bone marrow aspirate and biopsy were discordant in 19% of the cases. In 15% of the cases, bone marrow aspirate blast count was ≤ 5% and bone marrow biopsy blast percentage was >5%.

Conclusion: Early response assessment plays an important role in management of acute myeloid leukemia. In patients with CD34-positive blasts, the CD34 IHC can improve the detection of residual blasts on Day 14 bone marrow biopsy in comparison with morphological assessment of blast percentage in bone marrow aspirate.

Keywords: Acute myeloid leukemia; early response.