Real Life Use of Imaging in the Management of Newly Diagnosed Patients with Myeloma- Practical Perspectives from a UK Hospital

Background: The role of imaging in myeloma has gained increasing importance over the past few years. Cross‐sectional imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI) and 18fluoro‐deoxyglucose (18F‐FDG) positron emission tomography (PET/CT) have increased sensitivity of detection of myeloma bone lesions compared to skeletal plain radiographs. However, there is huge variation in practice both within the United Kingdom and internationally, as to the choice of modality due to differences in access to the techniques and the subtleties of the information gained from each type of imaging. At present whole body (WB) diffusion weighted (DW) MRI is not yet available in our hospital.

Aim: To review compliance of our current practice with the 2017 British Society for Haematology (BSH) guideline "Use of imaging in the management of patients with myeloma". To review the number of imaging modalities performed in newly diagnosed myeloma patients.

Audit Standard Criteria range: 100%, or if not achieved, there is documentation in the case notes that explains the variance.

• Patient with suspected myeloma underwent whole body MRI (WB-MRI) or CT (unless excluded due to unsuitability of procedure for the patient).

• Patient without established myeloma defining event (MDE) but with bone marrow plasma cells 10-60% and/or M-protein >30g/l underwent WB-MRI, WB-CT or PET/CT.

• WB/DW-MRI or PET/CT performed in the assessment of oligosecretory myeloma.

• Whole spine MRI performed and reported within 24 hours of suspected cord compression in myeloma.

• PET/CT or WB/DW-MRI performed in the diagnostic assessment of possible solitary plasmacytoma.

Method: Data collection period was between 1st July 2017 to 30th June 2018. We included all adult patients (age at least18 years) who were newly diagnosed with myeloma or plasmacytoma in our Trust during the data collection period, and had their diagnostic imaging in our Trust.Data were retrospectively collected from multidisciplinary meeting lists, chemotherapy list, radiology department data and electronic patient record (EPR).

Results: Forty patients were included in the audit, which included 31 myeloma patients, 8 smouldering myeloma patients, one plasmacytoma patient. There were no non-secretory or oligosecretory myeloma cases and there were no newly diagnosed myeloma patients presenting with suspected cord compression in our Trust during the data collection period.

All patients (100%) with suspected myeloma underwent cross-sectional imaging at diagnosis. Twenty nine (73%) patients had low dose (LD) WB-CT, four (10%) had PET/CT and one (2%) had WB-MRI. Eleven (27%) had CT chest abdomen pelvis (CT-CAP) ; this latter group of patients came through the suspected cancer referral pathway. No skeletal surveys were performed for patients with newly diagnosed myeloma or plasmacytoma during the data collection period. All smouldering myeloma patients underwent LDWB-CT. All solitary plasmacytoma patients had PET/CT or WB/DW-MRI.

Twenty out of 40 (50%) patients had more than one imaging modality. For the majority of these patients this comprised a CT and MRI whole spine/pelvis (40%) and 10% had a CT and PET-CT. Two patients had three modes of imaging. The main reasons for requesting MRI spine/pelvis were back pain, CT showed lytic lesion or mass in spine, CT showed equivocal lytic lesion or abnormal marrow signal in spine, CT showed no lytic lesion but clinically strongly suspected lytic lesion in spine. The main reasons for requesting PET/CT were CT showed equivocal lytic lesion, and suspected cancer.

Conclusion: Our Trust has excellent compliance with the BSH guideline as all new myeloma patients underwent cross-sectional imaging with a CT. However, for half of these patients CT alone was inadequate to fully assess their bone disease, requiring an additional modality.

Discussion: Patients with suspected myeloma are referred to the haematology department through different pathways, most commonly suspected myeloma and back pain (73%), and suspected cancer (27%). The route of referral often determines first imaging modality. For many patients more than one modality is required to accurately assess their bone disease, eg presence of focal lesions, active lesions, spinal cord compromise. This causes delay of making diagnosis and increased cost. Access to WB-DWI/MRI may address some if not all these issues.