No abstract

No abstract

Background Bone marrow failure syndrome (BMFS) is a heterogeneous group of disorders associated with single- or multiple-lineage cytopenia and failure of normal hematopoiesis. We assessed the feasibility of integrated PET/MRI with 3′-deoxy-3′- 18 F-fluorothymidine ( 18 F-FLT) to assess the pathophysiology of whole-body bone marrow for the diagnosis and monitoring of BMFS. Twenty-five consecutive patients with BMFS underwent a pre-treatment 18 F-FLT PET/MRI scan. They included 7 patients with aplastic anemia (AA), 16 with myelodysplastic syndrome (MDS), and 2 with myeloproliferative neoplasms (MPNs), primary myelofibrosis (MF), and secondary [post-essential thrombocythemia (post-ET)] MF. Two of the seven AA patients underwent a post-treatment scan. Eight of the 16 MDS patients who exhibited decreased 18 F-FLT uptake in the pelvis were considered to have hypoplastic MDS (hypo-MDS). 18 F-FLT PET and diffusion-weighted imaging (DWI) were visually and quantitatively evaluated. Results The 18 F-FLT uptake in the ilium was strongly correlated with bone marrow cellularity based on biopsy samples (ρ = 0.85). AA patients exhibited heterogeneously decreased uptake of 18 F-FLT according to disease severity. Multiple 18 F-FLT foci were observed in the proximal extremities, and they were in the central skeleton in severe AA patients. Post-treatment 18 F-FLT PET scans of severe AA patients reflected the response of hematopoietic activity to treatment. MDS patients had marked 18 F-FLT uptake in the central skeleton and proximal extremities, whereas hypo-MDS patients had heterogeneously decreased uptake, similar to that of non-severe AA patients. 18 F-FLT PET and DWI were unable to predict the progression to leukemia for both MDS and hypo-MDS patients. A primary MF patient had slightly decreased 18 F-FLT uptake in the central skeleton, but marked expansion of bone marrow activity to the distal extremities and high uptake of tracer in the extremely enlarged spleen (extramedullary hematopoiesis). In contrast, a secondary (post-ET) MF patient demonstrated marked bone marrow uptake, reflecting the hypercellular marrow with fibrosis. DWI revealed diffusely high signal intensities in both the primary and secondary MF patients. Conclusion 18 F-FLT PET can be used to noninvasively assess whole-body bone marrow proliferative activity and DWI may reflect the different aspects of bone marrow pathophysiology from 18 F-FLT PET. 18 F-FLT PET/MRI is useful for the diagnosis and monitoring of BMFS, except for the differentiation between non-severe AA and hypo-MDS, and the prediction o...

The primary objective of the present study was to correlate blood cell counts (lymphocyte, monocyte and platelet counts) with early disease relapse following the attainment of complete remission (CR) by the rituximab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP)-like regimen in patients with advanced diffuse large B-cell lymphoma (DLBCL). In total, 30 patients were evaluated, with a median follow-up period of 43 months. All the participating patients attained CR. In total, eight patients experienced relapse within two years of the diagnosis, and the three-year overall survival rate was recorded as 77%. The peripheral counts for lymphocytes, monocytes and platelets, and the lymphocyte-monocyte ratio, all of which have been reported to be prognostic in DLBCL, were assessed. None of these parameters were correlated with the incidence of early relapse or with the prognosis. The lymphocyte count was higher in the patients with durable remission than in those who relapsed, however, no significant differences were identified. Thus, the present study concluded that early disease relapse was not predicted by peripheral blood cell counts in advanced DLBCL that reached CR using the R-CHOP-like regimen.

We identified predictors for bone-marrow [ 18 f]fDG uptake and MR signals among complete blood count, C-reactive protein (CRP), and anthropometric factors, and demonstrated the bone-marrow physiology using integrated [ 18 F]FDG-PET/MRI. 174 oncology patients without bone-marrow lesions underwent whole-body [ 18 F]FDG-PET/MRI. The standardized uptake value (SUV), apparent diffusion coefficient (ADC), proton density fat-fraction (PDFF), and a reciprocal of T2* relaxation time (R2*) were measured in lumbar vertebrae (L3-5) and bilateral ilia. Vertebrae, pelvis, and ribs were evaluated by 3-point visual scoring on DWI. The association of the PET/MR features with the predictors was examined. Multi-regression analyses identified CRP as the strongest predictor for lumbar and iliac SUVs (standardized coefficient: β = 0.31 and β = 0.38, respectively), and for lumbar and iliac R2* (β = 0.31 and β = 0.46, respectively). In contrast, age was the strongest factor influencing lumbar and iliac ADCs (β = 0.23 and β = 0.21, respectively), and lumbar and iliac PDFFs (β = 0.53 and β = 0.54, respectively). Regarding DWI-visual scores, age was the strongest predictor for vertebrae (β = − 0.47), and the red cell distribution width (RDW) was the strongest predictor for pelvis and ribs (β = 0.33 and β = 0.47, respectively). The bone-marrow [ 18 F]FDG uptake and R2* reflect anemia of inflammation (increased granulopoiesis and reduced iron metabolism), whereas bone-marrow DWI and PDFF reflect age and anemia-responsive erythropoiesis. Abbreviations [ 18 F]FDG 2-[ 18 F]-fluoro-2-deoxy-D-glucose PDFF Proton density fat fraction R2* Reciprocal of the T2* relaxation time Hb Hemoglobin RDW Red cell distribution width WBC White blood cell CRP C-reactive protein GCSF Granulocyte colony-stimulating factor CBC Complete blood count eGFR Estimated glomerular filtration rate MR-AC Magnetic resonance based attenuation correction OSEM Ordered subset expectation maximization SUV Standardized uptake value EPI Echoplanar imaging STIR Short inversion time inversion recovery SSRF Spectral-spatial radiofrequency