The invisible enemies: COVID-19 and Multiple Myeloma

Binod Dhakal, Anita D'Souza, Saurabh Chhabra, Parameswaran Hari, Medical College of Wisconsin Milwaukee, WI, USA

By June 2020, the pandemic spread of SARS-CoV-2 virus causing COVID-19 disease has caused more than 6 million cases of COVID-19 and 370,472 deaths with more than 100,000 deaths directly attributable just in the US alone. Since the majority of infected patients make a full recovery without currently known sequelae, many studies have looked into the risk factors for COVID-19 severity and mortality. Age, diabetes, hypertension and cancer are the most common identified risk factors. Patients with cancer are considered a highly vulnerable group to COVID-19 given the immunosuppressive state caused by anti-cancer treatments and some cancers themselves.  When we decided to analyze pattern of COVID-19 in MM, specific data relating to hematological malignancies and MM were not available.

Multiple myeloma (MM), a cancer of antibody producing plasma cells is unique in its association with an acquired humoral immune deficiency state due to an underlying predominantly humoral immune deficiency. Prior studies have shown that MM patients carry almost 7-10-fold higher risk of bacterial and viral infections and have suboptimal responses to vaccines. The sudden death of one of our otherwise healthy COVID-19 positive MM patient due to cardiac arrest prompted us to investigate our own series and formed the basis of the study. We found that COVID-19 disproportionately affects older and African American patients (AA) (who are also at higher risk of having myeloma). The risk of infection was independent of MM status as patients on observation (smoldering MM), induction, early relapse and late relapses were all represented in our series. Community transmission was the most common mode of disease acquisition as only one had clear history of known exposure to another patient. The case fatality rate (CFR) was 57% in our series and nearly all needed intensive care unit care underscoring the severity of the disease.

Our study conveys several vital messages regarding the fallout of COVID-19 in MM. The high CFR rates observed in our series (similar to other studies which included all patients with hematological malignancies) and increased severity in older and AA highlight the toll in vulnerable. On the other hand, while it is important to limit the risks of COVID-19, it is equally important to provide an optimal and timely therapy for MM as well. Balancing the risk of potentially lethal infection against the risk of a destructive and ultimately fatal cancer is a concern of patients and their physicians. In addition to rising medication and therapy costs, pre-existing disparities in access to quality care and outcomes, the most vulnerable subgroup (elderly and AA) are now facing an even bigger challenge in care with deferral of therapy and many clinical trials on hold. Consensus guidelines developed by experts are constrained by the newness of the pandemic and limited evidence. For each patient, physicians need to weigh the personal risks from COVID-19 as well as that of deferred care against the benefits of optimal myeloma control. Our experience suggests that while the risk of mortality from COVID-19 is very worrying, community infection control remains the most important modifiable risk factor. Patient and physicians need to participate in shared decision-making in these difficult choices.