Monoclonal gammopathy of undetermined significance

Last reviewed: 29 Aug 2023
Last updated: 10 May 2023



History and exam

Key diagnostic factors

  • at-risk demographic (male, age >50 years, African ancestry)
  • clinically asymptomatic
  • positive family history
  • history of radiation exposure
  • history of pesticide exposure
More key diagnostic factors

Other diagnostic factors

  • history of immunosuppression or infections
  • presence of peripheral neuropathy
Other diagnostic factors

Risk factors

  • male sex
  • age >50 years
  • African ancestry
  • family history of MGUS or multiple myeloma
  • immune-mediated conditions
  • radiation exposure
  • pesticide exposure
More risk factors

Diagnostic investigations

1st investigations to order

  • electrophoresis with immunofixation and measurement of serum immunoglobulins
  • CBC with differential
  • serum calcium
  • serum creatinine
  • urinalysis and 24-hour urine collection with electrophoresis and immunofixation
  • serum free light chains assay
  • metastatic bone survey (conventional x-ray or whole body low-dose CT scan)
More 1st investigations to order

Investigations to consider

  • bone marrow aspiration and/or biopsy
  • bone mineral density scan
  • MRI scan
  • PET scan
More investigations to consider

Treatment algorithm


confirmed MGUS



Shaji Kumar, MD

Professor of Medicine

Division of Hematology

Mayo Clinic




SK has received research funding for clinical trials to the institution from Abbvie, Amgen, Allogene, Astra-Zeneca, BMS, Carsgen, GSK, Janssen, Novartis, Roche-Genentech, Takeda and Regeneron. SK has participated in consulting and advisory board activities (with no personal payments) for Abbvie, Amgen, BMS, Janssen, Roche-Genentech, Takeda, Astra-Zeneca, Bluebird Bio, Secura Biotherapeutics, Trillium, Loxo Oncology, K36, Sanofi, ArcellX, and (with personal payment) Oncopeptides, Beigene and Antengene.


Professor Shaji Kumar would like to gratefully acknowledge Dr Ola Landgren, a previous contributor to this topic.


OL is an author of several references cited in this topic.

Peer reviewers

Daniel Catovsky, MD

Consultant Haemato-Oncologist

Section of Haemato-Oncology

Brookes Lawley Institute of Cancer




DC declares that he has no competing interests.

  • Monoclonal gammopathy of undetermined significance images
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    Monoclonal gammopathy of undetermined significance

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