Table 1 Characteristics of clonal B cell and plasma cell proliferative disorders

MGUS

Any

<10%

Any

<30 g/l

None

Smouldering MM^a

Plasma cell

10–60%

Any

 ≥30 g/l

None

MM^a

Plasma cell

 ≥10%

Any

 ≥30 g/l

SLiM CRAB: 60% bone marrow plasma cells, involved:uninvolved free light-chain ratio >100, >1 bone lesion on MRI, hypercalcaemia, renal impairment, anaemia and lytic bone lesions

Smouldering WM^a

Lymphoplasmacytic lymphoma clone^b

 ≥10%

IgM

 ≥30 g/l

Absent

WM^a

Lymphoplasmacytic lymphoma clone^b

 ≥10%

IgM

 ≥30 g/l

Anaemia, hyperviscosity, constitutional symptoms, bulky lymphadenopathy, hepatosplenomegaly and neuropathy

MBL

B-cell clone^c

Peripheral B-cell count <5 × 10⁹/l

Any

Any

Absence of lymph node involvement

CLL

B-cell clone^c

Peripheral B-cell count >5 × 10⁹/l

Any

Any

Adenopathy, anaemia and thrombocytopenia

Other B cell lymphoproliferative disorders

Pan B-cell markers (CD19⁺CD20⁺CD79⁺CD22⁺PAX5⁺)

Presence or absence

Any

Any

Adenopathy and splenomegaly