When should I consider referring a patient with MGUS to a specialist for further evaluation or management?

Consider referring a patient with monoclonal gammopathy of undetermined significance (MGUS) to a specialist for further evaluation or management if:

• There is suspicion or evidence of progression to myeloma, such as persistent bone pain (particularly back pain) or unexplained fractures.
• Serum protein electrophoresis or serum free light chain testing suggests myeloma rather than stable MGUS.
• Urine Bence–Jones protein is positive, especially if serum free light chain testing is unavailable, combined with symptoms like persistent bone pain or unexplained fractures.
• There are abnormal laboratory or clinical findings that raise concern for myeloma or related plasma cell disorders.

Referral should be made using a suspected cancer pathway to ensure timely specialist assessment and management.

This approach aligns with NICE guidance on myeloma diagnosis and management, which emphasises prompt referral when clinical or laboratory features suggest progression beyond MGUS NICE NG35,NICE NG12.