Role of high acquisition flow cytometry in the detection of marrow involvement in patients with extramedullary B cell non-Hodgkins lymphoma: a comparison with marrow aspirate cytology, trephine biopsy, and PET

Abstract

Detection of marrow infiltration is crucial in extramedullary B cell non-Hodgkin lymphoma (B-NHL). We studied the efficiency of high acquisition flow cytometry (FCM) in detecting marrow involvement in B-NHL patients and compared its performance with marrow aspiration (BMA) cytology, marrow biopsy (BMB), and positron emission tomography (PET). No case with marrow infiltration was found to be BMB positive and FCM negative. BMA cytology showed poor sensitivity and specificity. Only 50% of FCM positive cases showed evidence of marrow involvement by PET. Neither the nature of lymphoma nor the burden of the marrow disease showed a correlation with PET positivity. Four cases that were positive only by PET had findings in areas other than the iliac region. We found more cogent and convincing results with high event acquisition in FCM. This study shows that a combination of PET and FCM with high event acquisition is the best way for assessing marrow involvement in B-NHL cases.

Keywords:

• Flow cytometry
• non-Hodgkin lymphoma
• bone marrow involvement
• bone marrow biopsy
• FDG-PET
• lymphoma staging

Acknowledgments

The authors would like to acknowledge Dr Arun Kumar, Assistant Professor, Department of Clinical Hematology, Christian Medical College, Vellore, for reviewing the manuscript. Mr Selvaraj and Mr Ellappan, flow cytometry technologist, Department of Hematology for their efforts in sample processing, acquisition and data retrieval. The authors would also like to acknowledge Ms Mirunalini and Mr Devarajan, Secretaries, Department of Hematology for data retrieval.

Disclosure statement

No potential conflict of interest was reported by the author(s).