Managing multiple myeloma.

Multiple myeloma is the second most common malignant hematologic disease in Canada

The incidence of multiple myeloma in Canada is 55 per 1 000 000 people, and the prevalence is increasing.1 Novel therapies, such as immunomodulatory drugs and proteasome inhibitors, have increased progression-free 5-year survival from 29% in 1997 to 68% in 2014 among patients who have received autologous stem cell transplantation.2

All patients with multiple myeloma should be referred early for assessment of transplant eligibility

Eligibility for therapy, including autologous stem cell transplant, is determined not only by age and renal function, but also by comorbidities and functional status.3 All-cause mortality rates 100 days post-transplantation are similar for younger (40–60 yr) compared with older (≥ 60 yr) patients (1% v. 2%).3

Bisphosphonates are recommended for all patients with multiple myeloma, regardless of evidence of bone disease

Zoledronic acid and pamidronate prevent osteopenia, lytic disease and fractures. Dosing and frequency depend on indications and risk factors.4 Use of more potent intravenous bisphosphonates, however, increases the risk of osteonecrosis of the jaw; regular dental assessments can reduce associated risks.

Prophylactic antibiotics, immunoglobulin replacement and inactivated vaccines may mitigate infections

Disease- and treatment-related factors confer a 10-fold and sevenfold increased risk of viral and bacterial infections, respectively, for patients with multiple myeloma.5 Prophylactic fluoroquinolone is often prescribed by the specialist team within the first 3 months of diagnosis for patients beginning active treatment.5 In patients with frequent or severe infections, immunoglobulin replacement, with or without long-term antibiotics, may be considered. Inactivated influenza and pneumococcal polysaccharide vaccines should be administered to all patients.

Clinicans should have a low threshold for performing skin biopsies of new lesions with concerning features

Patients with multiple myeloma have an increased risk of skin cancer, independent of age and ethnicity.6 In particular, the rate of squamous cell carcinoma is 2.4 times higher than for age-matched controls.6