A 70-year-old presents with bone marrow showing 15% plasma cells, serum M-protein of 2.8 g/dL IgG kappa, but no lytic lesions, anemia, hypercalcemia, or renal insufficiency. Fluorescence in situ hybridization (FISH) reveals t(4;14) translocation. The WHO 2022 classification would categorize this as:

• A Smoldering multiple myeloma ✓
• B MGUS (monoclonal gammopathy of undetermined significance)
• C Multiple myeloma requiring treatment due to t(4;14)
• D Plasma cell leukemia

Explanation

Smoldering multiple myeloma (SMM) is defined by serum M-protein ≥3 g/dL OR urine M-protein ≥500 mg/24h OR bone marrow plasma cells 10–60%, without CRAB criteria (hyperCalcemia, Renal insufficiency, Anemia, Bone lesions) or biomarkers of malignancy. This patient has 15% bone marrow plasma cells and 2.8 g/dL M-protein, meeting SMM criteria. The t(4;14) translocation is a high-risk cytogenetic feature that increases progression risk to active myeloma but does not by itself mandate treatment; it categorizes this as high-risk SMM per IMWG criteria.

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.