Canterbury DHB

Specific Complications of Myeloma

Bony or Nerve Compression Pain

The pain may reflect bone erosion or vertebral collapse, but nerve root or spinal cord compression by soft tissue infiltration without bony change can occur. Steroids and/or anti-inflammatories may be helpful, but Morphine is often required. A single fraction of localised radiotherapy can be used palliatively.

See Hospital HealthPathways – Pain in Cancer and Palliative Care.

For bone pain caused by local plasmacytoma, particularly when it is unresponsive to radiotherapy and controlled with analgesia, or bony strength is compromised, consider referral to Interventional Radiology Complex Oncology Musculoskeletal Procedures (COMP) for consideration of cementoplasty or cryo-ablation.

See Hospital HealthPathways – Musculoskeletal Procedures in Cancer Patients for referral instructions and forms.

Hypercalcaemia

The patient with hypercalcaemia may complain of nausea, vomiting, constipation, abdominal pain, thirst, and polyuria. Confusion and coma may supervene. This is a medical emergency. Usually admission is required if the calcium level is at 3.5 or higher.

• Treat with IV fluids to correct dehydration, 4-5 litres in 24 hours, both oral and/or IV. Start with 2 litres 0.9S over 2 hours, then 1 litre 0.9S 6-8 hourly until dehydration corrected. Fluid balance, and twice daily weights, will minimise the risk of fluid overload.
• Frusemide 20-40 mg PO or IV 12 hourly with potassium supplements will encourage diuresis and help lower plasma calcium.
• Prednisone 40-60 mg PO (or dexamethasone 40 mg PO daily)
• Bisphosphonates, e.g., Pamidronate 30 mg IV over 1 hour or zoledronic acid 4 mg IV over 20 minutes.

Spinal Cord Compression

Consider if there is back pain, particularly if this radiates around to the front of the chest or abdomen. Any weakness or numbness, or unsteadiness when walking should be noted. Urinary disturbance or constipation may also occur.

Note: If spinal cord compression is thought to be a possibility, immediate MRI is essential. The difficulty lies in interpreting symptoms that may be rather vague or ill-defined. Close follow-up needed if MRI is not done. Consultant involvement essential.

Infections

Immunoparesis, neutropenia, chemotherapy all combine to greatly increase the risk of infection. Bacterial infections, e.g., pneumococcal are common at presentation. Subsequently viral and fungal infections are common. The patient needs to be informed of these risks and of the need to contact the Department if they become febrile and/or unwell.

Recommendations made by the European Myeloma Network were updated in 2021.

Renal failure

This may be present at diagnosis or occur acutely if the patient is allowed to become dehydrated.

This is a difficult situation and confers a poor prognosis. However, careful fluid management to maintain a euvolaemic state and dialysis may reverse the acute renal failure. Renal function may return to normal if a good response is seen to chemotherapy.

Suitable chemotherapy in this situation consists of Dexamethasone 40 mg PO for 4 days, IV cyclophosphamide, bortezomib and/or thalidomide, VAD or ZDex.

Topic Code: 5604