A 58-year-old man found on routine testing has an IgG kappa M-protein of 24 g/dL. Bone marrow biopsy shows 14% clonal plasma cells. Haemoglobin 13.1 g/dL, corrected calcium 9.4 mg/dL, creatinine 0.9 mg/dL, skeletal survey shows no lytic lesions, and urine protein electrophoresis is negative. What is the most appropriate next step?
- A Start lenalidomide-based combination therapy
- B Observation with re-evaluation every 3 to 6 months ✓
- C Autologous stem cell transplantation after induction
- D Monthly zoledronic acid infusions
Correct answer: B. Observation with re-evaluation every 3 to 6 months
Explanation
Smouldering (asymptomatic) myeloma is defined by serum M-protein of 30 g/dL or more, or clonal bone marrow plasma cells of 10 percent or more, in the absence of any myeloma-defining event (CRAB features, amyloidosis, or biomarkers such as free light chain ratio above 100 or more than one focal lesion on MRI). His values fall short of these thresholds, so standard care is surveillance. Bisphosphonates are indicated only when lytic disease or osteoporosis warrants skeletal protection.
Reference: Harrison's Principles of Internal Medicine, 21st ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.