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

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 a 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 constitute a target population for MGUS screening. This two-part study is the first study to evaluate a relationship between 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=1.10; 95% confidence interval: 1.00-1.20). This excess risk was limited to prior cancers in the year preceding MGUS screening. A history of prior cancer was associated with progression of MGUS, except for myeloid malignancies which were associated with a lower risk of progression (hazard ratio=0.37; 95% confidence interval: 0.16-0.89; P=0.028). Our findings indicate that a prior cancer is not a significant etiological factor in plasma cell disorders. The findings do not warrant MGUS screening or different management of MGUS in those with a prior cancer.

Multiple myeloma incidence and mortality trends in the United States, 1999-2020

Multiple myeloma (MM) is a plasma cell disorder accounting for approximately 10% of hematologic malignancies. There is limited epidemiological evidence regarding the long-term trends and disparities in MM in the US. We conducted a multiple time point cross-sectional study using MM incidence rate data from the Surveillance, Epidemiology, and End Results (SEER) database and mortality data from the CDC Wide-Ranging Online Data for Epidemiologic Research (CDC WONDER) Underlying Cause of Death database between 1999 and 2020. During this period, MM incidence has steadily increased, while MM mortality has steadily decreased, with substantial racial and ethnic disparities. Non-Hispanic Black individuals exhibited the highest incidence rates, which consistently rose from 12.02 (95% CI 10.54, 13.64) in 1999 to 14.20 (95% CI 12.93, 15.55) per 100,000 population by 2020. Non-Hispanic American Indian/Native Alaskans and Asian/Pacific Islanders demonstrated the lowest incidence rates of 5.59 (95% CI 2.69, 10.04) and 3.56 (95% CI 2.94, 4.27) per 100,000 population in 1999 to 5.76 (95% CI 3.49, 8.90) and 3.92 (95% CI 3.46, 4.42) per 100,000 population, respectively, by 2020. Disparities by gender, age, US census region, and rurality were observed, underscoring the importance of targeted, equity-centered interventions and MM screening initiatives for at-risk populations.

Association of routine hematological parameters with the development of monoclonal gammopathies: a case-control study of 134,740 patients : Resubmitted to annals of Hematology 26 March 2024

The diagnosis of multiple myeloma requires detection of paraproteinemia and confirmation of monoclonal bone marrow infiltration, along with signs of end-organ damage. Despite the increasing prevalence, serum paraproteinemia is not routinely measured. We examined the relationship between alterations in routine hematological parameters and the development of paraproteinemia in a case-control study. Data was retrieved from a laboratory database in the capital region of Denmark between 01/01/2012 and 31/12/2022. Patients were included if they had a test for paraproteinemia (n = 134,740) and at least one prior hematological parameter (white blood cells, hemoglobin and platelet count) with a minimum follow-up of 1 year.Between 96,999 and 103,590 patients were included in each of the three hematological groups. We found white blood cell count and the presence of paraproteinemia followed an inverse J-shaped curve, with the highest presence below 3 × 109/L and above > 9 × 109/L. The adjusted OR below and above the nadir of 4 × 109/L was 1.61 (95% CI 1.25; 2.08, p < 0.0001) and 1.03 (95% CI 1.03; 1.04, p < 0.0001). Hemoglobin levels were inversely associated the presence of paraproteinemia, with the highest association below 6 mmol/L with an OR of 1.30 (95% CI 1.28; 1.32, p < 0.0001) adjusted for age and gender. Platelet count followed a U-shaped curve with the highest association at < 100 × 109/L. The adjusted OR below and above the nadir of 250 × 109/L was 1.13 (95% CI 1.10; 1.17, p < 0.0001) and 1.10 (95% CI 1.08; 1.12, p < 0.0001) respectively. In conclusion, all three parameters showed significant association with later paraproteinemia.

Association Between Autoimmune Diseases and Monoclonal Gammopathy of Undetermined Significance : An Analysis From a Population-Based Screening Study

BACKGROUND

Monoclonal gammopathy of undetermined significance (MGUS) is a precursor of multiple myeloma (MM) and related conditions. In previous registry-based, retrospective studies, autoimmune diseases have been associated with MGUS. However, these studies were not based on a screened population and are therefore prone to ascertainment bias.

OBJECTIVE

To examine whether MGUS is associated with autoimmune diseases.

DESIGN

A cross-sectional study within iStopMM (Iceland Screens, Treats, or Prevents MM), a prospective, population-based screening study of MGUS.

SETTING

Icelandic population of adults aged 40 years or older.

PATIENTS

75 422 persons screened for MGUS.

MEASUREMENTS

Poisson regression for prevalence ratios (PRs) of MGUS among persons with or without an autoimmune disease, adjusted for age and sex.

RESULTS

A total of 10 818 participants had an autoimmune disorder, of whom 599 had MGUS (61 with a prior clinical diagnosis and 538 diagnosed at study screening or evaluation). A diagnosis of an autoimmune disease was not associated with MGUS (PR, 1.05 [95% CI, 0.97 to 1.15]). However, autoimmune disease diagnoses were associated with a prior clinical diagnosis of MGUS (PR, 2.11 [CI, 1.64 to 2.70]).

LIMITATION

Registry data were used to gather information on autoimmune diseases, and the homogeneity of the Icelandic population may limit the generalizability of these results.

CONCLUSION

The study did not find an association between autoimmune disease and MGUS in a systematically screened population. Previous studies not done in systematically screened populations have likely been subject to ascertainment bias. The findings indicate that recommendations to routinely screen patients with autoimmune disease for MGUS may not be warranted.

PRIMARY FUNDING SOURCE

The International Myeloma Foundation and the European Research Council.

Early detection of multiple myeloma: A first step towards a screening programme

Novel therapies for multiple myeloma have substantially improved the prognosis, but before patients are able to benefit from treatment, a diagnosis must have been made. The Myeloma UK laboratory working group has developed a three-part tool box to help primary care physicians to suspect myeloma despite mostly vague symptoms, to do the right tests and to derive the proper conclusions from the results. Commentary on: Drayson et al. Laboratory practice is central to earlier myeloma diagnosis; utilising a primary care diagnostic tool and laboratory guidelines integrated into haematology services. Br J Haematol 2024;204:476-486.