Multiple Myeloma

A 58-year-old woman from Mumbai with newly diagnosed multiple myeloma (IgG-kappa type, 40% bone marrow plasma cells) undergoes staging investigations. Serum beta-2 microglobulin is 5.8 mg/L, serum albumin is 2.2 g/dL, and hemoglobin is 7.8 g/dL. Skeletal survey shows multiple lytic lesions in the spine and pelvis. She is started on bortezomib-based induction therapy. Which of the following complications is she at HIGHEST risk of developing during the first week of treatment?

Regarding the diagnostic criteria and laboratory findings in multiple myeloma, all of the following are true EXCEPT:

A 65-year-old man with newly diagnosed multiple myeloma undergoes serum protein electrophoresis. Which is the most common type of monoclonal immunoglobulin produced in multiple myeloma?

A 58-year-old woman presents with back pain, anemia, and elevated serum creatinine. Bone marrow biopsy shows 40% plasma cells. Which is the most common site of lytic bone lesions in multiple myeloma?

A 58-year-old woman with newly diagnosed multiple myeloma (IgG-κ type, 35% bone marrow plasma cells) is being staged. Which investigation is most appropriate to assess for extramedullary disease and spinal involvement?