A 63 year old man presented with back pain since few weeks. Blood investigation shows anemia, hypercalcemia and hypoalbuminemia. Serum protein electrophoresis (PEP) demonstrates an M spike. All of the following are MINOR criteria for diagnosis of multiple myeloma, EXCEPT:
Bone marrow plasmacytosis = 20% Multiple lytic lesions on skull X-ray Plasmacytoma on tissue biopsy Monoclonal spike < 3.5g/dL for IgG and < 2g/dL for IgA