Multiple Myeloma (MM)/ MGUS
Definition
Myeloma = abnormal proliferation of single clone of plasma (cf. CLL B cells) or lymphoplasmacytic cells leading to secretion of Ig or fragment, presenting as monoclonal Ig band or paraprotein
MGUS = Monoclonal gammopathy of uncertain significance = <30g/L protein OR < 10% plasma cells (no CRAB sx)
Smouldering MM = >30g/L protein OR >10% plasma cells (no CRAB sx)
MM = >30g/L protein + >10% plasma cells + CRAB sx
Epidemiology
Clinical Features
C alcium elevation (>2.8 mmol/L)
R enal failure (creatinine > 180mmol/L)
A naemia (hb < 100g/L)
B one disease (lytic lesions/ osteoporosis)
Investigations
Bedside: Urine (BJ protein)
Blood: Blood film (Rouleux formation = pile of coins), FBC (anaemia), UEC (renal failure), CMP (Ca2+), LFT (low albumin), LDH (high), beta2microglobulin (high), EPG (M band), IEPG (clonality), quantitative immunoglobulin (immune suppression)
Imaging: X ray (long bones), MRI/ CT/ PET (lytic lesions)
Others: Free light chain assay, cytogenetics/ FISH (fluoresence in situ hybridisation)
Management
MGUS: do nothing
MM
Source
Dr Ritam Prasad 2013
OHCM 9th Ed 2014
Complete PLAB EMQ 2004
Myeloma = abnormal proliferation of single clone of plasma (cf. CLL B cells) or lymphoplasmacytic cells leading to secretion of Ig or fragment, presenting as monoclonal Ig band or paraprotein
MGUS = Monoclonal gammopathy of uncertain significance = <30g/L protein OR < 10% plasma cells (no CRAB sx)
Smouldering MM = >30g/L protein OR >10% plasma cells (no CRAB sx)
MM = >30g/L protein + >10% plasma cells + CRAB sx
Epidemiology
- MGUS: 3.2% >50y; 9% > 85y (Not uncommon to detect paraprotein with elderly). Risk of transformation to MM is 1% per year, so do nothing
- MM will always be preceded by MGUS
Clinical Features
C alcium elevation (>2.8 mmol/L)
R enal failure (creatinine > 180mmol/L)
A naemia (hb < 100g/L)
B one disease (lytic lesions/ osteoporosis)
Investigations
Bedside: Urine (BJ protein)
Blood: Blood film (Rouleux formation = pile of coins), FBC (anaemia), UEC (renal failure), CMP (Ca2+), LFT (low albumin), LDH (high), beta2microglobulin (high), EPG (M band), IEPG (clonality), quantitative immunoglobulin (immune suppression)
Imaging: X ray (long bones), MRI/ CT/ PET (lytic lesions)
Others: Free light chain assay, cytogenetics/ FISH (fluoresence in situ hybridisation)
Management
MGUS: do nothing
MM
- Non transplantable = chemo (thalidomide/ steroids/ melphalan/ bortezomib - proteasome inhibitor)
- Transplantable = chemo --> stem cell transplant
Source
Dr Ritam Prasad 2013
OHCM 9th Ed 2014
Complete PLAB EMQ 2004