Diagnostic criteria for plasma cell myeloma
| Symptomatic plasma cell myeloma |
| M-protein in serum or urine* |
| BM clonal plasma cells or plasmacytoma† |
| Related organ or tissue impairment heavy chain disease‡ (CRAB) |
| Asymptomatic (smoldering) myeloma |
| M-protein in serum at myeloma levels (> 30 g/L) and/or ≥ 10% clonal plasma cells in BM |
| No related organ or tissue impairment end-organ damage or bone lesions [CRAB] or myeloma-related symptoms |
| Symptomatic plasma cell myeloma |
| M-protein in serum or urine* |
| BM clonal plasma cells or plasmacytoma† |
| Related organ or tissue impairment heavy chain disease‡ (CRAB) |
| Asymptomatic (smoldering) myeloma |
| M-protein in serum at myeloma levels (> 30 g/L) and/or ≥ 10% clonal plasma cells in BM |
| No related organ or tissue impairment end-organ damage or bone lesions [CRAB] or myeloma-related symptoms |
CRAB indicates hypercalcemia, renal insufficiency, anemia, bone lesions.
No level or serum or urine M-protein is included. M-protein in most cases is > 30g/L of IgG or > 25g/L of IgA or > 1g/24 h of urine light chain, but some patients with symptomatic myeloma have levels lower than these.
Monoclonal plasma cell usually exceed 10% of nucleated cells in the marrow, but no minimal levels are designated because ∼ 5% of patients with symptomatic myeloma have < 10% marrow plasma cells.
The most important criteria for symptomatic myeloma are manifestations of end-organ damage including anemia, hypercalcemia, lytic bone lesions, renal insufficiency, hyperviscosity, or recurrent infections.