MGUS

Question 1

What is MGUS pathophysiologically

Answer 1

premalignant clonal plasma cell or lymphoplasmacytic proliferative disorder

Question 2

what is a skeletal survey?

Answer 2

Series of X-rays of all the bones in the body, or at least the axial skeleton and the large cortical bones.

Question 3

MGUS vs. smoldering vs. multiple myeloma

Answer 3

MGUS = serum M protein <3 g/dL or with <10 percent clonal plasma cells in the bone marrow. + Absence of anemia, hypercalcemia, renal failure, and lytic bone lesions related to the plasma cell proliferative disorder
Smoldering = M protein >3 or >10 percent clonal plasma cells but no end organ damage from plasma cells

Question 4

3 distinct clinical types of MGUS

Answer 4

1) Non-IgM MGUS (IgG, IgA, IgD MGUS) (most common subtype)
2) IgM MGUS
3) Light chain MGUS

Question 5

IgM MGUS can progress to what?

Answer 5

• smoldering Waldenstrom macroglobulinemia

- symptomatic WM

Question 6

Which MGUS subtype is associated with higher risk of progression to MM?

Answer 6

IgM MGUS

Question 7

Risk factors for progression in MGUS

Answer 7

1) Serum M-protein level ≥1.5 g/dL [8,29-31]
2) Non-IgG MGUS (ie, IgA, IgM, IgD MGUS)
3) Abnormal serum free light chain (FLC) ratio (ie, ratio of kappa to lambda free light chains <0.26 or >1.65)

Question 8

Risk stratification based on risk factors and corresponding risk of progression to MM over 20 year period

Answer 8

1) 3 risk factors (high risk MGUS) – 58 percent
2) 2 risk factors (high-intermediate risk MGUS) – 37 percent
3) 1 risk factor (low-intermediate risk MGUS) – 21 percent
4) No risk factors (low risk MGUS) – 5 percent

Question 9

Paraproteins that are higher risk for myeloma progression

Answer 9

non-IgG