Plasma cell dyscrasias usually present with “CRAB” criteria of hypercalcemia, renal insufficiency, anemia, and lytic bone lesions. We describe a 66-year-old Caucasian gentleman who presented with a 3-month history of increasing yellow plaques in bilateral axillae and groin. Laboratory investigation revealed total cholesterol of 172 mg/dL, triglycerides of 37 mg/dL, HDL of 70 mg/dL and LDL of 95 mg/dL. Hemoglobin was 13.8 g/dL, calcium was 8.9 mg/dL, creatinine of 0.89 mg/dL. Punch biopsy of the skin revealed mononuclear cell infiltrate with numerous foamy histiocytic cells consistent with xanthoma. The pathologist recommended evaluation for plasma cell dyscrasia in light of normal cholesterol. Further testing demonstrated an IgG lambda monoclonal protein of 2.1 g/dL and kappa/lambda serum free light chain ratio of 0.56. A bone marrow biopsy revealed 20% IgG lambda clonal plasma cells. There was no evidence of lytic lesions on radiographs giving a diagnosis of smoldering myeloma. Treatment was deferred in light of no end organ damage. Since patient was not bothered by plaques, he was observed twice yearly (Fig. 1).
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