Evaluation of bone marrow aspirate and biopsy in the diagnosis of plasma cell myeloma

Objective To explore the value of bone marrow aspirate (BMA) and bone marrow biopsy (BMB) in the diagnosis of plasma cells myeloma (PCM).

Methods The distribution of plasma cells in BMA and BMB of 217 PCM patients was analyzed retrospectively in Zhongshan Hospital, Fudan University from October 2015 to January 2019. The relationship between BMA plasma cell numbers and patients' age and hematological results were also evaluated. The scatter diagram and fitting curve of plasma cells in two methods were made by SPSS, and the regression equation was obtained.

Results Among 190 patients with BMA plasma cells ≥10%, those with BMB plasma cells < 10% and plasma cells ≥10% accounted for 1.6% (3/190) and 98.4% (187/190), respectively. When BMA plasma cells > 60%, BMB plasma cells ≥10% in all patients. It was indicated that the two methods had high consistency in evaluating plasma cells in patients with plasma cells ≥10%. In contrast, among 27 patients with BMA plasma cells < 10%, those with BMB plasma cells < 10% and plasma cells ≥10% accounted for 11.1% (3/27) and 88.9% (24/27), respectively. It was inconsistent for two methods in diagnosis of PCM. β2-microglobulin in group with plasma cells ≥10% was higher than that in plasma cells < 10% group (P < 0.05), but there was no significant difference in calcium, creatinine, urea and albumin between the two groups. Equation was y＝11.13·x^0.39 (R²＝0.17).

Conclusion The combination of BMA and BMB may improve the accuracy of PCM diagnosis. Meanwhile, plasma cells can be preliminarily estimated by equation in order to judge curative effect or prognosis for patients only with BMA or BMB.