Feasibility of bone marrow infiltration pattern and ADC values for assessment of tumor burden using multi-parameter MR in multiple myeloma

MRI-based pattern and ADC assesses tumor burden for MM

Abstract

Objective

The purpose of our study was to explore and compare the tumor burden of different bone marrow infiltration patterns and evaluate the feasibility of ADC value to identify patterns in multiple myeloma．

Materials and Methods

93 patients with newly diagnosed multiple myeloma and 23 controls had undergone routine MRI and DWI from January 2019 to November 2020. Five BM infiltration patterns were allocated according to routine MRI. The laboratory data and ADC values of patterns were analyzed and compared. ROC analysis was used to establish the best diagnostic ADC threshold value for identifying these patterns and distinguishing normal pattern from controls. Besides, the correlation between the ADC values of diffuse pattern and the plasma cells ratio was assessed.

Results

1. The values of hemoglobin, β2-MG, plasma cell, M protein, the percentages of stage, high-risk fluorescence in situ hybridization, and ADC values showed significant difference among patterns.
2. ADC_mean at a specific value (368.5×10^-6 mm²/s) yielded a maximum specificity (95.5%) and sensitivity (92.0%) in diagnosing multiple myeloma. A specific value (335.5×10^-6mm ²/s) yielded a maximum specificity (84.7%) and sensitivity (88.0%) in discriminating visually normal pattern in multiple myeloma from controls.
3. There was a moderate positive correlation between the plasma cells ratio and ADCs of diffuse infiltration patterns (r=0.648, P<0.001)．

Conclusions

The bone marrow infiltration patterns in multiple myeloma patients can indicate the tumor burden and ADC value has the ability to discriminate these patterns objectively.