Efficacy of chemical shift MRI for differentiating diffuse red bone marrow reconversion and hematological malignancies

Abstract

Introduction Normal bone marrow contains water, fat, and cellular elements. The red bone marrow (RBM) contains 40% of water (free and bound), 20% of protein, and 40% (25%-50%) of fat. In contrast, the yellow bone marrow (YBM) contains 15% of water, 5% of protein, and 80% of fat (1-4). In newborns, the bone marrow consists mainly of active RBM. After the infantile period, the RBM begins to transform into YBM. When the active bone marrow is not able to meet the increased hematopoiesis required by the body, YBM converts to RBM, and this process is called reconversion (3-7). The causes of reconversion can be classified under medical and nonmedical conditions. Medical conditions include obesity, respiratory disorders, diabetes, anemias, patients receiving granulocyte colony stimulating factor therapy, chemotherapy, and radiotherapy. Nonmedical conditions include heavy smoking and practicing sports requiring high oxygen such as marathon running or freediving (2,5-7). Magnetic resonance imaging (MRI) is an ideal noninvasive imaging modality for evaluating bone marrow Background/aim: The main purpose of our study was to determine the efficacy of chemical shift imaging (CSI) for differentiating diffuse red bone marrow reconversion (RBMR) and hematological malignancies. We also aimed to calculate the cutoff value for these entities with similar imaging features in routine magnetic resonance (MR) sequences. Materials and methods: A total of 54 patients were included: 17 patients (31.4%) with hematological malignancies (group 1), 16 patients (29.6%) with RBMR (group 2), and 21 patients (38.0%) with no clinical and hematological malignancies (control group). Patients with no pathological data or completed two-year follow-up and children were excluded from the study. An experienced radiologist on MRI evaluated the images blindly for final diagnosis. Pathologic results were determined as gold standard. Regions of interests (ROI) were placed on the vertebrae in CSI and signal intensity ratios (SIR) were calculated. The cutoff value was calculated using receiver operating characteristic (ROC) analysis. Results: SIR values were 0.97 ± 0.16, 0.69 ± 0.31 and 0.28 ± 0.35 (P < 0.001) for GI, G2, and G3, respectively. The cutoff value was 0.82 (P < 0.001). The sensitivity rate was 83.3% (AUC: 58%-96%), specificity was 87% (AUC: 58-98). Conclusion: CSI may be a valuable diagnostic tool for differentiating diffuse RBMR and hematological malignancies.

Opposed Phase Imaging as a Diagnostic Biomarker for Differentiating Malignant from Benign Bone Marrow Lesions

“…On the other hand, the quantitative assessment of the signal drop was done by assessment of the signal intensity ratio (SIR) as done by Akman B et al, [22] & Amin, et al, [23] .…”

“…Amin, et al, [23] , proposed that ROC analysis of mean SIR for 25 benign and 38 malignant lesions, yielded threshold cut off value of 0.75 where malignant lesions were defined to be more than 0.75 and benign lesions were defined to be less than 0.75 with sensitivity, specificity, and AUC of 70.3%, 76.5%, and 0.694 for differentiating benign and malignant histology, respectively. Akman B, et al, [22] , selected a cut off point for SIR between benign and malignant vertebral lesions at value of 0.82, where values less than 0.82 are presumed benign while values higher are presumed malignant using the pathology as gold standard for comparison.…”

“…We followed the research model proposed by Akman B, et al, [22] which used ROC curve analysis to determine cut off value of SIR to differentiate malignant from benign lesions.…”

Value of third-generation of VNCa dual-energy CT for differentiating diffuse marrow infiltration of multiple myeloma from red bone marrow

“…The screening criteria of RBM were as follows: the MRI T1WI signal of the vertebral body was uniformly lower than or similar to the signal of the vertebral space; Follow-up for more than 1 year to exclude tumor and hematological diseases. [ 15 – 17 ]…”

“…The screening criteria of RBM were as follows: the MRI T1WI signal of the vertebral body was uniformly lower than or similar to the signal of the vertebral space; Follow-up for more than 1 year to exclude tumor and hematological diseases. [15][16][17] Because both MM and RBM had reduced T1WI signals, they were sometimes combined as signal reduction group later in this study.…”