Multiple myeloma is often diagnosed late, and improper diagnostic work ups can contribute to this delay. Most myeloma patients present in primary care, where providers may be less confident knowing what diagnostic testing to order.1 Combining serum free light chain (sFLC) testing with serum protein electrophoresis and immunofixation, as recommended by guidelines,2,3 enhances diagnostic sensitivity for multiple myeloma. Without sFLC testing, 1 in 8 myeloma cases may be missed.4