The following is the least useful investigation in multiple myeloma :
High-Yield Explanation
Answer is C (Bone scan) Bone scans are least useful for diagnosis of Multiple Myeloma. Cytokines secreted by myeloma cells suppress osteoblastic activity therefore typically no increased uptake is observed. In multiple myeloma the osteohlastic response to bone destruction is negligible. The bone scan therefore is often normal or may show areas of decreased uptake (photopenia).It has been found to be less useful in diagnosis than plain radiography. Ig protein /24 hour is a major ciriteria for diagnosis " align="left" height="133" width="100"> Note : Serum M component is most commonly IgG Q (IgG (53%), IgA (25%), IgD (I%) Bence Jones proteins are light chain protein only Q.