Development of a Multivariable Model to Predict the Need for Bone Marrow Sampling in Persons With Monoclonal Gammopathy of Undetermined Significance : A Cohort Study Nested in a Clinical Trial.

BACKGROUND: Monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM) are asymptomatic precursor conditions to multiple myeloma and related disorders. Smoldering multiple myeloma is distinguished from MGUS by 10% or greater bone marrow plasma cells (BMPC) on sampling, has a higher risk for progression, and requires specialist management. OBJECTIVE: To develop a multivariable prediction model that predicts the probability that a person with presumed MGUS has 10% or greater BMPC (SMM or worse by bone marrow criteria) to inform the decision to obtain a bone marrow sample and compare its performance to the Mayo Clinic risk stratification model. DESIGN: iStopMM (Iceland Screens, Treats or Prevents Multiple Myeloma), a prospective population-based screening study of MGUS. (ClinicalTrials.gov: NCT03327597). SETTING: Icelandic population of adults aged 40 years or older. PATIENTS: 1043 persons with IgG, IgA, light-chain, and biclonal MGUS detected by screening and an interpretable bone marrow sample. MEASUREMENTS: Monoclonal gammopathy of undetermined significance isotype; monoclonal protein concentration; free light-chain ratio; and total IgG, IgM, and IgA concentrations were used as predictors. Bone marrow plasma cells were categorized as 0% to 4%, 5% to 9%, 10% to 14%, or 15% or greater. RESULTS: The c-statistic for SMM or worse was 0.85 (95% CI, 0.82 to 0.88), and calibration was excellent (intercept, -0.07; slope, 0.95). At a threshold of 10% predicted risk for SMM or worse, sensitivity was 86%, specificity was 67%, positive predictive value was 32%, and negative predictive value was 96%. Compared with the Mayo Clinic model, the net benefit for the decision to refer for sampling was between 0.13 and 0.30 higher over a range of plausible low-risk thresholds. LIMITATION: The prediction model will require external validation. CONCLUSION: This accurate prediction model for SMM or worse was developed in a population-based cohort of persons with presumed MGUS and may be used to defer bone marrow sampling and referral to hematology. PRIMARY FUNDING SOURCE: International Myeloma Foundation and the European Research Council.

Prior cancer and risk of monoclonal gammopathy of undetermined significance: a population-based study in Iceland and Sweden.

There is some evidence that a prior cancer is a risk factor for the development of multiple myeloma (MM). If this is true, prior cancer should be associated with higher prevalence or increased progression rate of monoclonal gammopathy of undetermined significance (MGUS), the precursor of MM and related disorders. Those with a history of cancer might therefore present a target population for MGUS screening. This two-part study is the first study to evaluate the relationship of MGUS and prior cancers. First, we evaluated whether prior cancers were associated with having MGUS at the time of screening in the Iceland Screens Treats or Prevents Multiple Myeloma (iStopMM) study that includes 75,422 individuals screened for MGUS. Next, we evaluated the association of prior cancer and the progression of MGUS to MM and related disorders in a population-based cohort of 13,790 Swedish individuals with MGUS. A history of prior cancer was associated with a modest increase in the risk of MGUS (odds ratio (OR)= 1.10; 95% confidence interval (CI): 1.00-1.20). This excess risk was limited to prior cancers in the year preceding MGUS screening. A history of prior cancer associated with the progression of MGUS, except for myeloid malignancies which were associated with lower risk of progression (hazard ratio (HR)=0.37; 95%CI: 0.16-0.89; p=0.028). Our findings indicate that a prior cancer are not a significant aetiological factor in plasma cell disorders. The findings do not warrant MGUS screening or different management of MGUS in those with a prior cancer.

Determining hemodilution in diagnostic bone marrow aspirated samples in plasma cell disorders by next-generation flow cytometry: Proposal for a bone marrow quality index.

Hemodilution of bone marrow (BM) aspirates is a limitation of multiparameter flow cytometry (MFC) in plasma cell disorders. There is a need for a validated approach for assessing sample quality and the distribution of non-plasma cell BM populations by MFC could provide a solution. We evaluated BM-associated cell populations, assessed by next-generation flow cytometry (NGF) and white blood cell (WBC) count in 351 BM aspirated samples from 219 participants with plasma cell disorders in the Iceland Screens, Treats, or Prevents MM study (iStopMM), as markers of hemodilution by their discriminatory ability between first and (generally more hemodiluted) second pull BM aspirated samples. The most discriminating markers were used to derive a novel BM quality index (BMQI). Nucleated red blood cells and myeloid precursors provided the greatest discriminatory ability between first vs second pull samples (area under the curve (AUC): 0.87 and 0.85, respectively), significantly better than B cell precursors (AUC = 0.64; p < 0.001), mast cells (AUC = 0.65; p < 0.001), and the BM WBC count (AUC = 0.77; p < 0.05). We generated a novel BMQI that is intrinsic to current NGF protocols, for evaluating quality of diagnostic BM samples and suggest the use of a BMQI scoring system for interpreting results and guiding appropriate actions.

Disease associations with monoclonal gammopathy of undetermined significance can only be evaluated using screened cohorts: results from the population-based iStopMM study.

Monoclonal gammopathy of undetermined significance (MGUS) is an asymptomatic precursor condition that precedes multiple myeloma and related disorders but has also been associated with other medical conditions. Since systematic screening is not recommended, MGUS is typically diagnosed due to underlying diseases and most cases are not diagnosed. Most previous studies on MGUS disease associations have been based on clinical cohorts, possibly resulting in selection bias. Here we estimate this selection bias by comparing clinically diagnosed and screened individuals with MGUS with regards to demographics, laboratory features, and comorbidities. A total of 75,422 participants in the Iceland Screens, Treats, or Prevents Multiple Myeloma (iStopMM) study were screened for MGUS by serum protein electrophoresis, immunofixation and free light chain assay (clinicaltrials gov. Identifier: NCT03327597). We identified 3,352 individuals with MGUS, whereof 240 had previously been clinically diagnosed (clinical MGUS), and crosslinked our data with large, nationwide registries for information on comorbidities. Those with clinical MGUS were more likely to have at least one comorbidity (odds ratio=2.24; 95% confidence interval: 1.30-4.19), and on average had more comorbidities than the screened MGUS group (3.23 vs. 2.36, mean difference 0.68; 95% confidence interval: 0.46-0.90). They were also more likely to have rheumatological disease, neurological disease, chronic kidney disease, liver disease, heart failure, or endocrine disorders. These findings indicate that individuals with clinical MGUS have more comorbidities than the general MGUS population and that previous studies have been affected by significant selection bias. Our findings highlight the importance of screening data when studying biological and epidemiological implications of MGUS.

[Resistant hypertension - pheochromocytoma].

We report a case of a man with a 30-year history of treatment-resistant hypertension, hydropoiesis, tachycardic spells and dysgeusia. Despite repeated visits to the emergency department and work-up in an out-patient clinic, the diagnosis was unknown. Three years prior to remittance to an endocrinologist, the hypertension worsened, and he developed diabetes type-II. Further work-up revealed a 3 cm extra-adrenal pheochromocytoma, a paraganglioma. After surgical removal of the tumor, he is without medication and symptom free. Pheochromocytoma and paraganglioma are rare causes of hypertension, estimated to explain 0.1-0.6% of all cases, but nonetheless an important diagnosis to make, due to serious side effects.

Prevalence of smoldering multiple myeloma based on nationwide screening.

Smoldering multiple myeloma (SMM) is an asymptomatic precursor to multiple myeloma. Here we define the epidemiological characteristics of SMM in the general population in Iceland. The iStopMM study (ClinicalTrials.gov ID: NCT03327597 ) is a nationwide screening study for multiple myeloma precursors where all residents in Iceland 40 years or older were invited to participate. SMM was defined as 10-60% bone marrow plasma cells and/or monoclonal (M) protein concentration ≥3 g dl-1, in the absence of myeloma-defining events. Of the 80,759 who gave informed consent to participate, 75,422 (93%) were screened. The prevalence of SMM in the total population was 0.53% (95% confidence interval (CI) = 0.49-0.57%) in individuals 40 years or older. In men and women, the prevalence of SMM was 0.67% (95% CI = 0.62-0.73%) and 0.39% (95% CI = 0.35-0.43%), respectively; it increased with age in both sexes. For the 193 individuals with SMM, median age was 70 years (range 44-92 years) and 60% were males. The mean M protein concentration of individuals with SMM was 0.62 g dl-1 (range 0.01-3.5 g dl-1) and 73% had 11-20% bone marrow plasma cell infiltration. The high prevalence of SMM has implications for future treatment policies in multiple myeloma as the evidence supporting treatment initiation at the SMM stage is emerging.

Psychometric testing of the Icelandic Occupational Self-Assessment (OSA-IS).

BACKGROUND: The Occupational Self-Assessment (OSA) is a self-report measure of occupational competence and values used to identify goals and assess outcomes. The Icelandic version of the OSA (OSA-IS) has been through several developmental stages to evaluate its psychometric properties. Through each stage, revisions have been made. AIM: To investigate the psychometric properties of the fourth revised version of OSA-IS. MATERIALS AND METHODS: Retrospective data from 291 rehabilitation clients with a range of conditions were analysed using Rasch analysis of unidimensionality and descriptive statistics. All statistics were compared to established criteria. RESULTS: Analyses suggest the OSA-IS items define unidimensional constructs of occupational competence and values. Most (89%) participants completed the assessment in a reliable manner and no association was observed between demographic variables and fit status. Differences in the item hierarchies were observed between the original OSA and the OSA-IS, suggesting that Icelandic clients responded differently due to cultural, linguistic and/or sample differences. CONCLUSION AND SIGNIFICANCE: OSA-IS is a psychometrically sound instrument that may be used to support identification of client-centred goals and for intervention development. Clinicians should use score tables specifically developed for the OSA-IS to measure outcomes.

Social tie formation of COVID-19 students: evidence from a two-cohort longitudinal study.

The COVID-19 pandemic and the consequent move of higher education to online courses has disrupted the learning paths of many students. Social network data were collected from two cohorts of students, those starting their higher education in normal conditions in 2017 and those starting in 2020 during the pandemic. The findings showed that students in the 2020 cohort reported making fewer connections at the beginning of the first semester and developed significantly fewer connections during the first semester. Female students lost the relative advantage they had compared with male students in developing new connections. Based on our findings, and because of the importance of social connections made during the first year of study, the 2020 cohort will need considerable support in catching up with previous cohorts. The findings provide strong support for the assumption that online studies offer limited possibilities in building social connections compared with on-campus education.

Defining new reference intervals for serum free light chains in individuals with chronic kidney disease: Results of the iStopMM study.

Serum free light chain (FLC) concentration is greatly affected by kidney function. Using a large prospective population-based cohort, we aimed to establish a reference interval for FLCs in persons with chronic kidney disease (CKD). A total of 75422 participants of the iStopMM study were screened with serum FLC, serum protein electrophoresis and immunofixation. Estimated glomerular filtration rate (eGFR) was calculated from serum creatinine. Central 99% reference intervals were determined, and 95% confidence intervals calculated. Included were 6461 (12%) participants with measured FLCs, eGFR < 60 mL/min/1.73 m2, not receiving renal replacement therapy, and without evidence of monoclonality. Using current reference intervals, 60% and 21% had kappa and lambda FLC values outside the normal range. The FLC ratio was outside standard reference interval (0.26-1.65) in 9% of participants and outside current kidney reference interval (0.37-3.10) in 0.7%. New reference intervals for FLC and FLC ratio were established. New reference intervals for the FLC ratio were 0.46-2.62, 0.48-3.38, and 0.54-3.30 for eGFR 45-59, 30-44, and < 30 mL/min/1.73 m2 groups, respectively. The crude prevalence of LC-MGUS in CKD patients was 0.5%. We conclude that current reference intervals for FLC and FLC ratio are inaccurate in CKD patients and propose new eGFR based reference intervals to be implemented.

Monoclonal gammopathy of undetermined significance and COVID-19: a population-based cohort study.

Multiple myeloma (MM) patients have increased risk of severe coronavirus disease 2019 (COVID-19) when infected by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Monoclonal gammopathy of undetermined significance (MGUS), the precursor of MM has been associated with immune dysfunction which may lead to severe COVID-19. No systematic data have been published on COVID-19 in individuals with MGUS. We conducted a large population-based cohort study evaluating the risk of SARS-CoV-2 infection and severe COVID-19 among individuals with MGUS. We included 75,422 Icelanders born before 1976, who had been screened for MGUS in the Iceland Screens Treats or Prevents Multiple Myeloma study (iStopMM). Data on SARS-CoV-2 testing and COVID-19 severity were acquired from the Icelandic COVID-19 Study Group. Using a test-negative study design, we included 32,047 iStopMM participants who had been tested for SARS-CoV-2, of whom 1754 had MGUS. Among these participants, 1100 participants, tested positive, 65 of whom had MGUS. Severe COVID-19 developed in 230 participants, including 16 with MGUS. MGUS was not associated with SARS-CoV-2 infection (Odds ratio (OR): 1.05; 95% confidence interval (CI): 0.81-1.36; p = 0.72) or severe COVID-19 (OR: 0.99; 95%CI: 0.52-1.91; p = 0.99). These findings indicate that MGUS does not affect the susceptibility to SARS-CoV-2 or the severity of COVID-19.

Iceland screens, treats, or prevents multiple myeloma (iStopMM): a population-based screening study for monoclonal gammopathy of undetermined significance and randomized controlled trial of follow-up strategies.

Monoclonal gammopathy of undetermined significance (MGUS) precedes multiple myeloma (MM). Population-based screening for MGUS could identify candidates for early treatment in MM. Here we describe the Iceland Screens, Treats, or Prevents Multiple Myeloma study (iStopMM), the first population-based screening study for MGUS including a randomized trial of follow-up strategies. Icelandic residents born before 1976 were offered participation. Blood samples are collected alongside blood sampling in the Icelandic healthcare system. Participants with MGUS are randomized to three study arms. Arm 1 is not contacted, arm 2 follows current guidelines, and arm 3 follows a more intensive strategy. Participants who progress are offered early treatment. Samples are collected longitudinally from arms 2 and 3 for the study biobank. All participants repeatedly answer questionnaires on various exposures and outcomes including quality of life and psychiatric health. National registries on health are cross-linked to all participants. Of the 148,704 individuals in the target population, 80 759 (54.3%) provided informed consent for participation. With a very high participation rate, the data from the iStopMM study will answer important questions on MGUS, including potentials harms and benefits of screening. The study can lead to a paradigm shift in MM therapy towards screening and early therapy.

[Catamenial pneumothorax due to pulmonary endometriosis].

Endometriosis is a chronic condition causing menstrual pain, irregular bleeding and infertility among women. Although usually in the pelvis, it can manifest in atypical places. We describe a 39-year old woman with a previous endometriosis diagnosis who presented three times on the second menstrual day with dyspnea and chest pain. Imaging showed right-sided pneumothorax on all three occasions. Thoraco-scopy revealed endometriosis-like lesions. Histology was suggestive of endometriosis. After treatment with chemical pleurodesis and hormonal suppression she has remained symptom-free. Diagnosis should be obtained by concomitant thoraco- and laparoscopy with biopsies to verify the disease and give a basis for appropriate treatment.

[Tumors of unknown origin: Case report].

IgG4 related disease is a recently recognized chronic fibrotic, inflammatory condition, caused by infiltrating IgG4 positive plasma cells that can cause tumor like disease in almost any organ in the body. Typical histopathology is lymphoplasmocytic infiltration of IgG4 positive cells, storiform fibrosis and obliterative phlebitis. Glucocorticoids alone or in combination with B-cell depletion with rituximab causes often good, lasting response. We present here a lady with recurrent lung infiltration that simulated pneumonia and later tumor of the lung. She was also earlier diagnosed with lump in the breast that was found to contain similar IgG4 positive plasma cells that was also demonstrated in the lung biopsy. She responded very well to rituximab given on 2 occasions. Three years after this treatment she is in total remission. Key words: IgG4 related disease, rituximab treatment, plasmacytoma of breast, tumor of lung Correspondence: Arni Jon Geirsson, arnijon@landspitali.is.

[Recurrent tumor growth in the right maxilla--a rare case of an inflammatory myofibroblastic tumor]. / Sjaldgæft tilfelli af vöðvabandvefsæxli með bólgufrumuíferð í hægri kinnkjálka.

28 year old male with inflammatory myofibroblastic tumor in the right maxilla undergoes multiple surgeries for the removal of recurrent tumors over a period of 4 years and is without symptoms of recurrences today. Cells cultured from the tumor show stem cell properties that could contribute to the recurrent tumor growth. It is important to do a close follow up on patients with these traits and further recurrences cannot be excluded even though surgical edges are free of tumor growth.

Low rather than high Ki-67 protein expression is an adverse prognostic factor in diffuse large B-cell lymphoma.

The prognostic role of overexpression of Ki-67 protein in diffuse large B-cell lymphoma (DLBCL) is still unclear. Furthermore, immunohistochemical studies have suggested a correlation between markers of proliferation, B-cell differentiation and apoptosis, but the prognostic relevance of these findings has not been clarified. To investigate the prognostic impact of Ki-67, in the context of this correlation, a retrospective immunohistochemical study was performed on 199 DLBCL patients treated with curative intent. Patients with low Ki-67 expression (<49%) had significantly worse progression-free (PFS) and overall (OS) survival, independent of clinical risk factors. In addition, low Ki-67 correlated to bcl-2 expression but not to non-germinal centre B-cell-like (non-GCB) phenotype. Each of these factors had negative impact on PFS and OS, but low Ki-67 expression also remained as an adverse prognostic factor independent of non-GCB phenotype and bcl-2 expression. Together, these results suggest that low rather than high Ki-67 protein expression is of prognostic importance in DLBCL.

Expression of CD68+ tumor-associated macrophages in patients with diffuse large B-cell lymphoma and its relation to prognosis.

Tumor-associated macrophages (TAM) have been ascribed both pro- and anti-tumor properties, but the majority of clinical cancer studies have shown that the presence of a high number of TAM is related to poor prognosis, suggesting that TAM predominantly exert pro-tumoral activity. The prognostic role of TAM in patients with diffuse large B-cell lymphoma (DLBCL), however, is so far unknown. Therefore, TAM were immunohistochemically stained with a CD68 antibody in a retrospective, population-based study including 176 DLBCL patients treated with curative intent. With the exception that patients >60 years of age had a larger number of CD68+ cells (1143 vs 1018 cells/mm2; P = 0.05), no significant differences were found between the number of CD68+ cells and other clinical factors. Similarly, germinal center B-cell (GCB)/non-GCB immunophenotype or low/high Ki-67 percentage were not associated with CD68 expression. Finally, no significant correlation was found between the number of CD68+ cells and progression-free survival (P = 0.34) or overall survival (P = 0.94). These data indicate that the pro-tumor effect of TAM has limited clinical relevance in DLBCL patients, which could imply that therapeutic strategies aimed at enhancing their anti-tumor activity are of continuous clinical interest.

Linkage of osteoporosis to chromosome 20p12 and association to BMP2.

Osteoporotic fractures are a major cause of morbidity and mortality in ageing populations. Osteoporosis, defined as low bone mineral density (BMD) and associated fractures, have significant genetic components that are largely unknown. Linkage analysis in a large number of extended osteoporosis families in Iceland, using a phenotype that combines osteoporotic fractures and BMD measurements, showed linkage to Chromosome 20p12.3 (multipoint allele-sharing LOD, 5.10; p value, 6.3 x 10(-7)), results that are statistically significant after adjusting for the number of phenotypes tested and the genome-wide search. A follow-up association analysis using closely spaced polymorphic markers was performed. Three variants in the bone morphogenetic protein 2 (BMP2) gene, a missense polymorphism and two anonymous single nucleotide polymorphism haplotypes, were determined to be associated with osteoporosis in the Icelandic patients. The association is seen with many definitions of an osteoporotic phenotype, including osteoporotic fractures as well as low BMD, both before and after menopause. A replication study with a Danish cohort of postmenopausal women was conducted to confirm the contribution of the three identified variants. In conclusion, we find that a region on the short arm of Chromosome 20 contains a gene or genes that appear to be a major risk factor for osteoporosis and osteoporotic fractures, and our evidence supports the view that BMP2 is at least one of these genes.