Whole Body Low-Dose CT for Multiple Myeloma

Components and Features of WBLDCT in Multiple Myeloma

The National Comprehensive Cancer Network recommends whole body low-dose CT (WBLDCT) as the primary imaging modality for initial diagnosis and follow-up of multiple myeloma, due to its superiority over conventional skeletal surveys in detecting bone lesions 1, 2
WBLDCT extends from skull vertex to knees without intravenous contrast, with radiation doses of 3.2-4.8 mSv, as per the European Journal of Nuclear Medicine and Molecular Imaging 3
CT contrast agents are not necessary for detection of myeloma bone disease and should generally be avoided in myeloma patients, according to the National Comprehensive Cancer Network 1

WBLDCT detects osteolytic lesions that may be missed by conventional skeletal surveys, with 25.5% of patients showing positive findings on WBLDCT despite negative skeletal surveys, as reported by the National Comprehensive Cancer Network 4, 2
WBLDCT is particularly superior for detecting abnormalities in the spine and pelvis, as well as the skull and ribs, which are areas difficult to visualize with skeletal surveys 2, 5, 1

If PET/CT is chosen instead of WBLDCT, the CT component should have imaging quality equivalent to WBLDCT, not just for attenuation correction, as recommended by the National Comprehensive Cancer Network 1, 2
PET/CT offers additional value in detecting extramedullary disease outside the spine and metabolically active lesions that may not show structural changes 1, 5
MRI is particularly useful when WBLDCT or FDG PET/CT is negative, to help discern smoldering myeloma from active multiple myeloma, and provides superior soft tissue contrast, as per the European Journal of Nuclear Medicine and Molecular Imaging 1, 2, 3

The NCCN Panel recommends either WBLDCT or FDG PET/CT for initial diagnostic workup of patients suspected of having multiple myeloma, with skeletal survey including long bones acceptable only where advanced imaging is not available 2, 5, 1
For follow-up after primary treatment, advanced imaging (WBLDCT, FDG PET/CT, or whole-body MRI without contrast) should be used as clinically indicated, with the same imaging modality used during initial workup used for follow-up assessments for consistency 5, 7
The minimum assessment frequency of every 3 months during active treatment is recommended, as per Praxis Medical Insights 6