Skeletal survey and other imaging modalities, particularly in relation to myeloma diagnosis (know indications only)

Role

Imaging in suspected/confirmed multiple myeloma has evolved from the traditional skeletal survey (plain X-rays of the axial and proximal appendicular skeleton) toward more sensitive cross-sectional modalities (whole-body low-dose CT, MRI, or PET-CT) - the specific knowledge required is indications, reflecting this evolving imaging landscape
Bone disease (lytic lesions, pathological fracture) is one of the defining CRAB criteria for symptomatic myeloma, making imaging central to both diagnosis and ongoing disease assessment

Myeloma bone disease is predominantly osteolytic (from osteoclast activation via RANKL upregulation, with relatively little osteoblastic/reparative response) - explaining why bone scintigraphy (as used in most other cancers for bone metastasis detection) performs poorly in myeloma and is not the appropriate imaging modality here (see nuclear bone scan for this specific limitation)

Whole-body low-dose CT has largely replaced plain skeletal survey as the preferred initial imaging in most current guidelines, given substantially higher sensitivity for detecting lytic lesions with a comparable or lower radiation dose
MRI (whole-body or spine) is more sensitive still for detecting marrow infiltration and can identify disease before lytic bone destruction is visible on CT/X-ray
PET-CT provides both structural and metabolic information, useful for detecting extramedullary disease and assessing treatment response

Imaging findings (number/extent of lytic lesions, presence of extramedullary disease) inform diagnosis (a defining CRAB criterion), prognostic staging, and monitoring for skeletal complications requiring bone-protective therapy (bisphosphonates/denosumab) or orthopaedic intervention (pathological fracture)

Multiple myeloma diagnostic (CRAB) criteria, pathological fracture risk, bone-protective therapy (bisphosphonates, denosumab), MGUS/smouldering myeloma (imaging is a key distinguishing step from symptomatic myeloma)

Bone scintigraphy is specifically not recommended for myeloma bone disease given its osteolytic (not osteoblastic) pathology - a frequently tested point distinguishing myeloma imaging from the bone scan-based approach used for most solid tumour bone metastases

5 more sections, plus exam facts

Premium unlocks every note across every specialty, and the full exam fact library behind it.