Question

The immunoglobulin most commonly involved in multiple myeloma is:

• A. IgG
• B. IgM
• C. IgA
• D. IgD

Hint:

Pick the immunoglobulin class that makes up roughly half of all myeloma cases.

Answer 1

The Correct Option is A

Step 1: Multiple myeloma is a malignant clonal proliferation of plasma cells that secretes a single (monoclonal) immunoglobulin called the M component.

Step 2: The M component can be IgG, IgA, IgM, IgD, or IgE, or light chains alone, or rarely heavy chains alone. The frequencies differ widely between these classes.

Step 3: IgG myeloma is the most common type, accounting for roughly half of cases (about 52 percent), followed by IgA (about 22 percent), then IgM and light-chain disease. IgD (about 2 percent) and IgE (rare) are the least common.

Step 4: Because IgG is the single most frequent paraprotein in multiple myeloma, the correct answer is option a, IgG.