Chapter 2 – Diagnosis and staging

Contributors: Carlos Fernández de Larrea and Joan Bladé

4 – Imaging

Several imaging techniques can be used for the assessment of bone and soft-tissue involvement in MM [2,23]:

  • Skeletal survey remains the standard method for imaging screening at diagnosis and is readily available at a modest cost, although its limitations in sensitivity must be noted.
  • Magnetic resonance imaging (MRI) or computed tomography (CT) should be performed when extramedullary involvement (EM) is suspected (ie, non-skeletal severe localized pain, palpable masses, or suspected nervous system involvement [spinal cord compression or cranial nerve palsies]). An MRI of the spine and pelvis is mandatory in all patients with a presumed diagnosis of solitary plasmacytoma of the bone, spinal cord compression, and pre-kypho- or vertebroplasty [24]. MRI is also beneficial in evaluating patients with smoldering MM [2].
  • 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET/CT) may be particularly useful in extramedullary disease evaluation, allowing the measurement in size and metabolic activity of soft-tissue masses, similar to the lymphoma setting [24]. The IMWG states that 18F-FDG PET/CT is mandatory to confirm a suspected diagnosis of solitary plasmacytoma, provided that whole-body MRI is unable to be performed. It is also deemed mandatory to distinguish between smoldering and active MM, if whole-body X-ray is negative and whole-body MRI is unavailable [25]. It is also a useful tool in determining prognosis in patients with newly diagnosed and relapsed or refractory MM [25].