Beta 2-microglobulin Levels Research Articles

The Association between oxidative stress marker Beta-2 microglobulin and type 2 diabetes mellitus in context of glycaemic index

Beta-2 microglobulin (B2M) protein has been shown to be elevated in response to oxidative stress and metabolic disorders and it modulates human immune and inflammatory responses. However, little is known about the association between B2M and glycaemic index in diabetic patients. Hence, this case-control study was conducted to measure the effects of type 2 diabetes mellitus (T2DM) on the plasma concentrations of B2M. A total of 50 T2DM male patients alongside another 50 age-matched and healthy men were enrolled. The plasma concentrations of B2M and haemoglobin A1c (HbA1c) were measured. Data related to smoking, daily consumption of multivitamins and regular performance of exercise were obtained through a questionnaire. The participants body mass index (BMI) was calculated after the body weight (Kg) and height (cm) of each participant was recorded. The results showed comparable age, BMI and rate of active smoking between the study groups. However, the levels of HbA1c were significantly higher, whereas the frequencies of consuming multivitamins and regularly performing exercise were significantly lower, in the T2DM group when compared with healthy controls. The plasma B2M levels also showed moderate significant positive correlations with age, BMI, and HbA1c plasma levels. In conclusion, the plasma Concentration of the oxidative stress marker B2M, was associated with T2DM and a significant elevation in its levels was positively correlated with age and the levels of HbA1c.

Evaluation of beta-2 microglobulin, erythropoietin and tobacco use in polycythemic cases.

In the 2016 WHO classification, hemoglobin and hematocrit thresholds for diagnosing polycythemia vera (PV) have been lowered, increasing the number of consultations for polycythemia investigations. In PV, beta-2 microglobulin (B2m) levels are reportedly increased, whereas erythropoietin (EPO) levels are usually low. Most secondary polycythemia cases (SP) are caused by tobacco use. We decided to analyze the relevance of these three parameters in all patients seen for polycythemia investigations to help differentiate PV from SP cases. A cohort of 257 patients (123 PV; 134 SP) was identified. The median B2m level was higher for PV patients (3.16 vs 1.98mg/l, p < 0.0001). Increased B2m levels were observed in 83.7% of PV patients (11.9% in SP). The median EPO level was lower in PV patients (4.4 vs 12.3 UI/l, p < 0.0001). Tobacco was used by 42.8% of SP patients (8% in PV, p < 0.0001). Increased B2m, low EPO and no tobacco exposure was predictive of PV (specificity and positive predictive value = 100%). Normal B2m, normal EPO and tobacco exposure was predictive of SP (positive predictive value = 100%). These simple and inexpensive parameters could be used to rapidly differentiate PV from SP cases, before prescribing time-consuming JAK2 V617F mutation analysis by specialists.

Impact of beta-2 microglobulin expression on the survival of glioma patients via modulating the tumor immune microenvironment.

AimsHigh immune cell infiltration in gliomas establishes an immunosuppressive tumor microenvironment, which in turn promotes resistance to immunotherapy. Hence, it is important to identify novel targets associated with high immune cell infiltration in gliomas. Our previous study showed that serum levels of beta‐2 microglobulin (B2M) in lower‐grade glioma patients were lower than those in glioblastoma patients. In the present study, we focused on exploring the roles of B2M in glioma immune infiltration.MethodsA large cohort of patients with gliomas from the TCGA, CGGA, and Gravendeel databases was included to explore differential expression patterns and potential roles of B2M in gliomas. A total of 103 glioma tissue samples were collected to determine the distributions of B2M protein levels by immunofluorescent assays. Kaplan‐Meier survival analysis and meta‐analysis were used for survival analysis. GO(Gene‐ontology) enrichment analysis, co‐expression analysis, KEGG(Kyoto Encyclopedia of Genes and Genomes) pathway analysis, and immune infiltration analysis were performed to explore roles and related mechanisms of B2M in glioma.ResultsWe found that both B2M mRNA and protein levels were abnormally upregulated in glioma samples compared with those from normal brain tissue. B2M expression was correlated with tumor grade and was downregulated in IDH1 mutant samples. Furthermore, B2M was a moderately sensitive indicator for predicting the mesenchymal molecular subtype of gliomas. Interestingly, glioma patients with lower B2M expression had remarkably longer survival times than those with higher B2M expression. Moreover, meta‐analysis showed that B2M was an independent predictive marker in glioma patients. The results of GO enrichment analysis revealed that B2M contributed to immune cell infiltration in glioma patients. In addition, results of KEGG pathway analysis and co‐expression analysis suggested that B2M may mediate glioma immune infiltration via chemokines.ConclusionsWe conclude that B2M levels are critical for the survival times of glioma patients, at least in part due to mediating high immune infiltration.

Serum beta-2 microglobulin analysis in patients with oral squamous cell carcinoma.

Aim:This study aims to compare the level of serum beta-2 microglobulin (β2-M) in normal healthy individuals and patient with squamous cell carcinoma (SCC).Methodology:This study has been conducted in patients attending the Department of Oral and Maxillofacial Surgery, Yenepoya Dental College, Deralakatte, Mangalore. Sample comprises of 25 cases of clinically and histologically diagnosed oral cancer and 25 normal healthy individuals as control group. The serum was analyzed for β2-M by enzyme-linked immunosorbent assay.Results:It was observed that there was a significant increase in serum β2-M levels in oral SCC patients as compared to controls. Circulating levels in serum β2-M were also elevated significantly among different clinical stages with progressive rise from stage I to stage IV of the disease.Conclusion:The evaluation of these markers would be useful in assessing malignant change, increasing accuracy of clinical diagnosis and also in assessing the spread and invasiveness of the cancer of the oral cavity.

COMPARATIVE EFFICACY OF EXTRACORPOREAL SHOCKWAVE LITHOTRIPSY AND RETROGRADE INTRARENAL SURGERY IN THE TREATMENT OF CALCIUM OXALATE NEPHROLITHIASIS

Objective To evaluate the results of extracorporeal shockwave lithotripsy (ESWL) versus retrograde intrarenal surgery (RIRS) for the treatment of calcium oxalate nephrolithiasis, as well as the damaging effects on renal function, taking into account the dynamics of blood cystatin C and urine beta2-microglobulin.Material and Methods Of 94 patients with calcium oxalate nephrolithiasis aged 23–78 included in the study, 42 patients were classified as having undergone ESWL (group I) and 52 patients as having undergone RIRS (group II). Group II patients were then stratified into subset 2A (n = 32) as having undergone RIRS through rigid ureteroscope and subset 2B (n = 20) as having undergone RIRS through flexible ureteroscope. We performed plain urography and nephrosonography at 24–48 hours postoperatively and unenhanced computed tomography 4–6 weeks after surgery. We measured concentrations of serum cystatin C and urinary beta2-microglobulin as a marker for kidney damage. In group I, samples of peripheral blood andurine were taken before and after the first, third sessions and 30 days after the last ESWL session. In group II, samples were analyzed before surgery, on the first and 30th postoperative days.Results The average size of calculi in the group with RIRS was 16.91 ± 2.79 mm, in the group with ESWL 12.31 ± 2.27 mm. The need for reoperation after RIRS was 19.2%, which was lower than after ESWL. Stone-free effect (no stones, or residual stones less than 3 mm) was observed in 95% of cases in patients with RIRS, and in 78% with ESWL. Group I patients demonstrated an increase in the blood leukocytes total number more often than subsets 2A (rigid RIRS) and 2B (flexible RIRS) patients. Leukocyturia was also a more common complication in group I. In the RIRS group, there was no statistically significant change in the level of blood cystatin C and urine beta2-microglobulin, on the contrary, a moderate increase in the endogenous marker of cystatin C was noted after one ESWL session. The increase in urine beta2-microglobulin levels in patients after the first and third ESWL sessions was significantly higher than after RIRS.Conclusion Flexible RIRS may be suggested as the preferred procedure for patients requiring additional protection of renal function in the treatment of renal stones less than 20 mm. ESWL of stones less than 20 mm can be used as an alternative treatment, since it is characterized by a rather long period of stone eradication from the urinary tract, a high frequency of residual calculi after the procedure, and also has a damaging effect on the renal tissue.

CD4 T Cell-Dependent Rejection of Beta-2 Microglobulin Null Mismatch Repair-Deficient Tumors.

Inactivation of beta-2 microglobulin (B2M) is considered a determinant of resistance to immune checkpoint inhibitors (ICPi) in melanoma and lung cancers. In contrast, B2M loss does not appear to affect response to ICPis in mismatch repair-deficient (MMRd) colorectal tumors where biallelic inactivation of B2M is frequently observed. We inactivated B2m in multiple murine MMRd cancer models. Although MMRd cells would not readily grow in immunocompetent mice, MMRd B2m null cells were tumorigenic and regressed when treated with anti-PD-1 and anti-CTLA4. The efficacy of ICPis against MMRd B2m null tumors did not require CD8+ T cells but relied on the presence of CD4+ T cells. Human tumors expressing low levels of B2M display increased intratumoral CD4+ T cells. We conclude that B2M inactivation does not blunt the efficacy of ICPi in MMRd tumors, and we identify a unique role for CD4+ T cells in tumor rejection. SIGNIFICANCE: B2M alterations, which impair antigen presentation, occur frequently in microsatellite-unstable colorectal cancers. Although in melanoma and lung cancers B2M loss is a mechanism of resistance to immune checkpoint blockade, we show that MMRd tumors respond to ICPis through CD4+ T-cell activation.This article is highlighted in the In This Issue feature, p. 1601.

Beta 2 microglobulin in kidney failure: A review and an algorithm for renal replacement therapy.

For decades, beta 2 microglobulin (B2M) has been a subject of great interest in nephrology and other fields such as multiple myeloma. B2M, a 99 amino acid protein, is associated with amyloid deposits in patients undergoing renal replacement therapy (RRT). The source of information is published articles on B2M in chronic renal failure since 1960. We have reviewed literature published since 1960 to date, highlighting the milestones of the role of B2M in chronic kidney disease (CKD) and B2M serum values in patients treated by various RRTs. B2M deposits associated with the disease include carpal tunnel syndrome, spondyloarthropathy, and arthritis of large joints such as the shoulders. The role of RRT in the removal of B2M in CKD is discussed. Recent reports include factors affecting the process of fibrillation and deposition of B2M in tissues. A comparative report of various modalities of treatment on the serum levels of B2M is provided. The presence of significant residual urine output in continuous ambulatory peritoneal dialysis patients may explain why peritoneal dialysis is a modality that is associated with the lowest level of serum B2M. Patients treated with hemodiafiltration or hemodialysis (HD) using high flux dialyzers have lower levels of B2M than those treated by HD with low flux dialyzers. Finally, based on the literature review, an algorithm for RRT using B2M level monitoring and other variables is proposed and needs evaluation in a controlled trial.

Single-cell transcriptomics following ischemic injury identifies a role for B2M in cardiac repair

The efficiency of the repair process following ischemic cardiac injury is a crucial determinant for the progression into heart failure and is controlled by both intra- and intercellular signaling within the heart. An enhanced understanding of this complex interplay will enable better exploitation of these mechanisms for therapeutic use. We used single-cell transcriptomics to collect gene expression data of all main cardiac cell types at different time-points after ischemic injury. These data unveiled cellular and transcriptional heterogeneity and changes in cellular function during cardiac remodeling. Furthermore, we established potential intercellular communication networks after ischemic injury. Follow up experiments confirmed that cardiomyocytes express and secrete elevated levels of beta-2 microglobulin in response to ischemic damage, which can activate fibroblasts in a paracrine manner. Collectively, our data indicate phase-specific changes in cellular heterogeneity during different stages of cardiac remodeling and allow for the identification of therapeutic targets relevant for cardiac repair.

Correlations of serum beta 2-microglobulin level with disease activity and renal involvement in patients with systemic lupus erythematosus

Abstract Objectives To determine correlations of serum beta 2-microglobulin (β2-MG) level with disease activity and renal involvement in patients with systemic lupus erythematosus (SLE). Methods Two hundred eligible SLE patients were assigned into remission and active stage groups according to SLE disease activity index (SLEDAI) scores. They were also assigned into kidney damage and no kidney damage groups. Serum β2-MG, Scr, ALB, BUN, anti-dsDNA, complements C3, C4 and 24-h urinary total protein (UTP) were detected. Estimated glomerular filtration rate (eGFR) was calculated. Correlations of β2-MG level with SLEDAI score and eGFR were subjected to Spearman analysis. Affecting factors were explored by logistic multivariate regression analysis, and predictive values of β2-MG level for SLE, disease activity and renal damage were assessed by ROC curves. Results β2-MG, Scr, ALB, C3, C4, anti-dsDNA and UTP levels, eGFR and SLEDAI score were different between patients with different disease activities, and, except for eGFR, also between patients with different renal damage degrees (p&lt;0.05). Serum β2-MG, Scr, ALB, C3, C4, anti-dsDNA, UTP, eGFR and SLEDAI score were independent factors for disease activity (p&lt;0.05), and β2-MG, ALB, C3, UTP, eGFR and SLEDAI score were factors affecting renal damage (p&lt;0.05). β2-MG level was correlated positively with SLEDAI score (r=0.877, p=0.000) and negatively with eGFR (r=−0.873, p=0.000). This level was highly valuable for predicting SLE, disease activity and renal damage. Conclusions Serum β2-MG levels in SLE patients are correlated positively with disease activity and negatively with renal involvement, being highly sensitive and specific for predicting SLE, disease activity and eGFR.

Design and methodology of the chronic kidney disease as a dysmetabolic determinant of disability among older people (CKD-3D) study: a multicenter cohort observational study

BackgroundChronic kidney disease (CKD) is a common condition in older people and represents a global health issue since it increases the risk of associated comorbidities and all-cause mortality. Furthermore, older people with reduced renal function might be at higher risk for developing functional limitation and disability. Moreover, the current creatinine-based measures of renal function are influenced by several factors in older population. The aims of the CKD-3D project are to perform an observational study to expand the knowledge about CKD-disability relationship and to investigate the use of novel biomarkers of kidney function.MethodsAn observational, multicenter, prospective cohort study will be conducted in 75 + old patients consecutively admitted to acute care wards of geriatric medicine at participating hospitals. The study planned to enroll 440 patients undergoing clinical and laboratory evaluations at baseline and after 12 months. Face-to-face follow-up at 6 months and telephone follow-up at 3 and 9 months will be carried out. Comprehensive Geriatric Assessment (CGA) and the measurement of Cystatin C, Beta-Trace Protein and Beta2-Microglobulin levels will be included.DiscussionThis study will provide useful information to prevent CKD-related disability by collecting real-life data over 1-year period. The combined approach of CGA and the investigation of innovative existing biomarkers will make it possible to develop new recommendations and guidelines for a patient-centered approach. It is believed that such a study may lead to an improvement of knowledge on CKD in elderly patients and may also have implications in daily clinical practice and in decision-making process.

First-week urine beta-2 microglobulin levels in term healthy neonates.

Beta-2 microglobulin (β2mG) is a low-molecular-weight protein that is almost exclusively eliminated through the kidneys. It is freely filtered in the glomeruli and almost completely reabsorbed and degraded in the proximal tubules. Normal urinary β2mG levels are very low (between 0.04 and 0.22 mg/L). No reference values are known in infants and young children. Urinary β2mG levels were measured in 103 healthy term neonates during the first week of life by nephelometric technology. The average level of urinary β2mG was 0.65 mg/L (95% confidence interval between 0 and 10.8 mg/L). There was a minor difference between male and female neonates but it did not reach statistical significance. There was no effect of the gestational week, birth weight, or weight loss in the first week of life, on urinary β2mG levels. First-week urinary β2mG levels in healthy term infants were higher than adult levels. Incomplete maturation of kidney tubules in neonates could be a possible explanation. These can now be used in clinical practice and further studies that assess the degree of proximal tubular function in health and disease. Graphical abstract.

Investigation of Urinary Beta-2 Microglobulin Level in Neonates with Asphyxia Admitted in Alzahra Hospitals in Isfahan, 1396-1397

Background: Despite advances in perinatal care, perinatal asphyxia (PA) remains one of the most important causes of mortality and morbidity at birth. Asphyxia is associated with the dysfunction of different organs of the body. Therefore, this study aimed to investigate the urinary biomarker of beta-2 microglobulin in neonates with asphyxia. Methods: This case-control study was performed on neonates admitted to the Neonatal Intensive Care Unit of AL Zahra and Shahid Beheshti hospitals affiliated to Isfahan University of Medical Sciences, Isfahan, Iran, during 2017-18. On the second day of birth, beta-2 microglobulin was measured in urine samples using the enzyme-linked immunosorbent assay technique. Results: The mean level of beta-2 microglobulin in the group with asphyxia (9.91±6.16) was significantly higher than that in the control group (3.83±4.03) (P=0.001). Moreover, analysis of beta-2 microglobulin level in the group with asphyxia showed that the mean serum level of neonates with acute renal failure (13.14±6.27) was significantly higher than that in newborns without acute renal failure (6.68±4.24) (P=0.02). Conclusion: The results of our study suggest that the beta-2 microglobulin level can be evaluated as a marker of neonatal asphyxia. Furthermore, its level was significantly associated with acute kidney injury. It is suggested that further studies be conducted with a larger sample size.

Lactate dehydrogenase, Beta-2 Microglobulin Levels and CD4/CD8 Lymphocyte Ratio in Patients with Mycosis Fungoides in Stage 1A

Objective: Mycosis fungoides is the most common type of primary cutaneous T-cell lymphomas. In this study, we aimed to investigate the biochemical parameters of beta-2 microglobulin, lactate dehydrogenase, CD4/CD8 lymphocyte ratio determined by flow cytometry, and T cell clonality in patients with MF and to correlate these parameters in stage 1A and other stages.&#x0D; Materials and Methods: A hundred sixty-one (87 Male, 74 Female) patients followed-up between January 1995 and January 2019 were retrospectively evaluated. Patients’ demographics, stage of the disease, peripheral lymph node and organ involvement, peripheral blood beta-2-microglobulin, lactate dehydrogenase levels, CD4/CD8 + lymphocyte ratio and presence of T cell clonality in biopsy samples were evaluated.&#x0D; Results: Median beta-2 microglobulin levels were 1608.5 ng/ml for stage 1A and 1970.5 ng/ml for other stages. Peripheral blood median CD4/CD8 lymphocte ratio was 1.60 for stage 1A and 1.85 for other stages. We found statistically significant difference between two groups in terms of beta-2 microglobulin levels and peripheral blood median CD4/CD8 lymphocte ratio (p=0.001, p=0.04). No statistically significant difference was found between two groups in terms of lactate dehydrogenase levels and T-cell clonality (p=0.234, p=0.525).&#x0D; Conclusion: Our study supports that high peripheral blood beta-2 microglobulin level and CD4/CD8 lymphocyte ratio at the time of diagnosis may imply advanced stage and poor prognosis in Mycosis Fungoides.

Beta 2 microgloblin increase prognosis effectiveness in aggressive diffuse large b-cell lymphoma and high clinical risk

Introduction: We conducted an open label clinical to assess if beta 2 microglobulin (B2M) can be useful as prognostic factor that can increase the usefulness of International Prognostic Index (IPI)in patients with aggressive lymphoma ; with stage IV and high clinical risk. Methods: Between January 1999 to December 2015, 1388 patients with aggressive lymphoma ,in that were classified as high-clinical risk and stage IV, treated with CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) or R-CHOP (CHOP+rituximab); B2M was adding to the staging procedures; they were classified in two groups: normal (&lt; 3.0 mg/L) or elevated ( &gt;3.0 mg/L) levels that were compared in response type and outcome. Results: Complete response, actuarial curves of progression-free survival and overall survival, were statistically better in patients with normal levels of B2M: 68%; 78% (95% Confidence interval(CI):(69% - 83%)) and 73%(95%CI: 67%-82 %) ; and 73% (95%CI:67%-81%) compared with patients with high levels were: 54%; 58%(95%CI; 48%-67%); and 47% (95%CI:39%-58%), (p &lt;0.001) respectively. Multivariable analysis confirm that B2M and lactate dehydrogenase have powerful to detect a worse prognostic course. Conclusion: B2M appear to be a no-expensive, simple and reproducible marker to help defined an worse prognosis in patients with high clinical risk and advanced stage. Thus, will be considered to planned a clinical trial to test the efficacy of different chemotherapeutic regimens in these setting of patients.

The impact of dyslipidemia on early markers of endothelial and renal dysfunction in children

BackgroundDyslipidemia has been associated with endothelial dysfunction in childhood. Impairment of renal function has been demonstrated in dyslipidemic adults. ObjectiveThe aim of this study was to assess markers of early endothelial and renal dysfunction in dyslipidemic children. MethodsThis was a cross-sectional study of 100 children with dyslipidemia and 100 age- and sex-matched control subjects without dyslipidemia aged 7–16 years. Renal dysfunction was assessed by measurement of serum creatinine and cystatin C levels, urinary beta 2-microglobulin levels, urinary albumin to creatinine (Alb:Cr) ratio, and by the estimated glomerular filtration rate (eGFR), based on serum creatinine or cystatin C. Endothelial dysfunction and early vascular changes were evaluated by ultrasound assessment of flow mediated dilation (FMD) of the brachial artery, and carotid intima-media thickness (cIMT), respectively. ResultsThe markers of early renal dysfunction showed no difference between the dyslipidemic children and control subjects except for the urinary Alb:Cr ratio that was higher in the dyslipidemic children (median, 0.007 mg/mg vs 0.005 mg/mg, p = 0.004). The urinary Alb:Cr ratio was positively correlated with the triglyceride to high-density lipoprotein cholesterol ratio (r = 0.28, p = 0.013). FMD values were lower in the dyslipidemic children than in the control subjects (8.504 ± 4.73% vs 10.535 ± 4.35%, p = 0.004), but cIMT did not differ between groups. This decrease in FMD values was evident in children aged ≥10 years. FMD was independently associated with the level of lipoprotein (a) (beta = −0.29, p = 0.01). ConclusionAmong markers of endothelial and renal dysfunction investigated, FMD was found to be lower and the urinary Alb:Cr ratio higher in children with dyslipidemia.

Potential association between elevated serum human epididymis protein 4 and chronic kidney disease in female patients.

Serum levels of human epididymis protein 4 (HE4) are elevated in a large number of women with chronic kidney disease (CKD). However, it remains unclear whether HE4 can be used as a potential biomarker for the diagnosis of CKD. This study aims to determine whether serum HE4 is a potential biomarker for CKD in Han Chinese female patients. A total of 347 Han Chinese female patients aged 19 to 89 were included in the present study. Among these patients, 154 were healthy control individuals, while 193 were hospitalized patients with CKD. Their demographic characteristics were obtained, and the levels of serum creatinine (Scr), beta2-microglobulin (B2M), and cystatin C (CysC) (to assess renal function) were measured. Serum HE4 concentration was determined by electrochemiluminescence. Serum HE4 levels in patients with CKD were significantly higher than those in the control group (P < 0.001). Meanwhile, there were significant differences in HE4 levels among the four CKD subgroups (P < 0.001) via multiple comparisons. In addition, the diagnostic value of HE4 was significantly higher than other indicators by ROC curve analysis. HE4 may not only serve as a potential biomarker to predict CKD but also have an important reference value for CKD staging.

Serum Levels of Beta-2 Microglobulin in Rheumatoid Arthritis Patients and its Relationship with Disease Activity: Can it be used as a Disease Activity Marker?

Abstract Background Beta-2 microglobulin (β2M) is mainly released from activated lymphocytes. Increased serum β2M levels have been shown in autoimmune diseases. The aim of this study was to analyse the serum levels of β2M in rheumatoid arthritis (RA) patients and to evaluate its relationship with disease activity measures. Material and Methods This cross-sectional study included 137 RA patients, 102 ankylosing spondylitis patients (AS) and 50 healthy controls (HC). To assess the disease activity of RA patients, the 28-joint Disease Activity Score-Erythrocyte Sedimentation Rate (DAS28-ESR), the 28-joint Disease Activity Score-C-Reactive Protein (DAS28-CRP), the Simplified Disease Activity Index (SDAI) and the Clinical Disease Activity Index (CDAI) were used. A p value of &lt;0.05 was considered statistically significant. Results Serum β2M levels were significantly higher in RA patients (2.95±1.19 mg/L) compared with HC (2.21±0.54 mg/L) and AS patients (2.200.58 mg/L) (p&lt;0.001). There was a statistically significant correlation between β2M levels and DAS28-ESR (rs=0.359, p&lt;0.001), DAS28-CRP (rs=0.293, p=0.001), SDAI (rs=0.332, p&lt;0.001) and CDAI (rs=0.291, p=0.001). Serum β2M levels were higher in the RA group with DAS28-ESR ≥3.2 (3.30±1.42 mg/L) than in the DAS28-ESR &lt;3.2 group (2.67±0.87 mg/L) (p=0.002). Conclusion Our study revealed that serum β2M levels were higher in RA patients than in healthy controls, and, in contrast to other studies, we found positive correlations between β2M levels and RA disease activity measures.

Bone Marrow Infiltration at Diffuse Large B-Cell Lymphoma NOS Diagnosis: Comparative Study between PET, Histology and Flow Cytometry

Introduction Bone marrow (BM) examination at diffuse large B-cell lymphoma (DLBCL) diagnosis is essential in staging and has prognostic implication. According to the last recommendations (Cheson, et al. JCO 2014) BM biopsy (BMB) is only needed for those patients with a negative BM infiltration by positron emission tomography (PET) for whom identification of occult discordant histology - whose biological and prognostic implications are unknown - is clinically important. Despite its greater sensitivity, flow cytometry (FC) is secondary in BM assessment. Our aim was to compare PET, BMB and FC in the study of BM infiltration at DLBCL diagnosis. Methods Retrospective study in two hospitals in Madrid of patients diagnosed with DLBCL NOS from January 2014 to January 2020. A complete BM assessment including PET, BMB and FC was performed in all included patients. The hole series (n=102) was analysed separately according with BM infiltration by each technique, differences between biological, clinical and laboratory variables were studied applying descriptive statistics tests when appropriate (Fisher's exact test, chi-square test, Student's T test and Mann-Witney U test). Event-free survival (EFS) and overall survival (OS) were analysed with Kaplan-Meier estimator according to BM infiltration positive vs negative for each technique, using Cox proportional-hazard model for comparisons. Results BM infiltration was not assessed in 2 patients by BMB and in 4 patients by FC due to technical reasons. Analysing separately the series according to BM infiltration by each technique (PET+ 25 vs PET- 77, BMB+ 15 vs BMB- 85 and FC+ 16 vs FC- 82) the basal characteristics were comparable between groups, except from extranodal sites ≥2, Ann Arbor III-IV and elevated LDH level in groups with positive BM infiltration. The variables associated with worsen EFS in univariate analysis were age ≥80 years (HR 2.31; CI 95% 1.1-5.1), cell-of-origin (COO) non-GCB (HR 2.33; CI 95% 1.1-4.9), extranodal sites ≥2 (HR 2.39; CI 95% 1.2-4.7), Ann Arbor III-IV (HR 4.55; CI 95% 2.0-10.5), and elevated LDH level (HR 2.32; CI 95% 1.1-4.7). The variables statistically related with worsen OS were COO non-GCB (HR 2.91; CI 95% 1.2-6.8), extranodal sites ≥2 (HR 2.61; CI 95% 1.2-5.5), Ann Arbor III-IV (HR 5.97; CI 95% 2.1-17.3), elevated LDH level (HR 2.36; CI 95% 1.1-5.4), and elevated beta-2 microglobulin level (HR 3.82; CI 95% 1.1-12.9). Double-expressor phenotype did not demonstrated association with EFS or OS. Median infiltration by FC analysis was 0.9% (0.05-27). The series distribution among BM infiltration is presented in Figure 1. Median follow-up was 25 months (0.3-90). Survival curves according to BM infiltration by PET, BMB and FC are presented in Figure 2. Univariate analysis among the type of infiltration by each technique are presented in Table 1. Multivariate analysis included age ≥80 years, COO non-GCB, BM FC+ and IPI score 3-5; BM infiltration by FC demonstrated no association with EFS (HR 2.2; CI 95% 0.9-5.3) or OS (HR 2.5; CI 95% 0.9-6.5). Conclusions BM infiltration by PET at DLBCL NOS diagnosis has not survival implication, contrary to infiltration demonstrated by BMB or FC. Cases with positive infiltration by PET but negative by BMB and FC could be false positive in PET or false negative in BMB/FC. According to our results the patients with discordant lymphoproliferative disorder BM infiltration presented worse prognosis and FC is probably the most important technique in this regard. Disclosures No relevant conflicts of interest to declare.

ABCL-099: CNS Prognostic Index Impacts on Overall Survival in a Cohort of Patients with DLBCL Treated with RCHOP in a Single Mexican Institution

Context: The Central Nervous System International Prognosis Index (IPI CNS) scale has an impact to assess central nervous system relapse risk and prognosis in patients with diffuse large B-cell lymphoma (DBLCL). Objective: Determine the impact of clinical, biochemical parameters, and the IPI SNC scale in relapse and survival in Mexican population. Design: Retrospective analysis. IRB approved the review of files. Setting: Our study was developed in a cancer reference center. Patients or other participants: Inclusion criteria: patients ≥ 18 years of age, with DLBCL, treated with CHOP-rituximab at the Instituto Nacional de Cancerologia Mexico, from 2011 through 2018. Clinical characteristics included age, gender, comorbidities (diabetes mellitus, blood arterial hypertension, cardiopathy), the presence of B symptoms, bulky disease, clinical stage, IPI SNC scale, performance status (ECOG). Biochemical parameters: Lactic Dehydrogenase (LDH), and beta2 microglobulin levels, as well as histological subtype of DLBCL. Main outcome measures: Descriptive analysis. Kaplan-Meier method and differences between subgroups were compared with Log-Rank test. Cox regression analysis was used to identify the variables predicting on progression-free survival and overall survival. Results: Six hundred and forty-two cases were included. Mean age was 56.8 years, most of patients were in adequate performance status (ECOG 0-1: N=484, 75%), with absence of B-symptoms, but with advanced disease (clinical stage: III-IV, N= 433, 67.4%). According to IPI CNS, almost the half of them were in the low-risk category. Clinical response was considered as complete in most of patients (n=455, 71%). The CNS relapse rate was: 4/293 (1.36%), 10/322 (3.1%), and 2/27 (7.4%) for patients in low-, intermediate-, and high-risk categories, respectively. Mean overall survival (OS) was 46.36 months, and after Cox regression analysis, only the prognosis scores IPI & IPI-CNS scale were statistically significant on OS; median OS has not been achieved at 80 months of follow-up in low-risk group, in comparison with 22 months in high-risk group (p=0.001). Conclusions: In this population the IPI CNS scales impacted not only on CNS relapse but also in OS; therefore, the usefulness of this prognostic index becomes relevant in our population.

Clinical Experience in Carotid Body Tumors:imaging techniques and surgical approaches

Objectives: At the time of diagnosis, 20 to 30% of multiple myeloma (MM) patients have renal failure. International Staging System (ISS) is based on 2 variables: serum levels of albumin and beta 2-microglobulin (B2M). Serum B2M level increases in patients with renal failure. This means that the elevated serum level of B2M is not always correlated with tumor burden in MM patients who have renal failure. Therefore, these patients may have further ISS stages than they really have. In this study, we aim to evaluate the success of ISS in predicting survival in MM patients with renal failure.Method: The data of 172 MM patients that underwent autologous stem cell transplantation (ASCT) at our center were retrospectively analyzed. The patients were divided into 5 renal function stages according to the Renal Disease Quality Classification of the National Kidney Foundation.Results: Overall survival (OS) after ASCT was found 21 months in ISS1 patients, 20 months in ISS2 patients, and 18 months in ISS3 patients. OS in stage 0-1 patients was 18 months, it was 30 months in stage 2-3-4-5 patients. There was no statistically significant difference regarding OS between patients with renal failure and normal renal function in all ISS stages.Conclusion: Our data reveals that the significance of ISS to predict overall survival is independent from renal failure.