Routine antiemetic prophylaxis with dexamethasone during COVID-19: Should oncologists reconsider?

The ongoing pandemic caused by severe acute respiratory syndrome (SARS) coronavirus type 2 (SARS-CoV-2, also known as COVID-19) has caused unprecedented strain on the global healthcare system, causing thousands of deaths worldwide. Patients with underlying conditions such as cancer are at substantial risk of acquiring and dying from this novel coronavirus. Numerous reports have shown that infection with SARS-CoV-2 causes depletion of B- and T-lymphocytes, including CD4 and CD8 T-cells, and is associated with severe illness and death and that patients with higher lymphocyte levels may have better outcomes. Dexamethasone, a widely prescribed antiemetic for acute and delayed nausea and vomiting from a variety of cancer drugs, causes B and T cell depletion, which may augment immunosuppression. Since it seems that lymphocytes are vital in the immune response to novel coronavirus, oncologists should reconsider the routine use of prophylactic dexamethasone in uninfected patients, to avoid inducing lymphopenia, which may increase risk of infection or lead to inferior outcomes if a cancer patient subsequently becomes infected. Since many cancer drugs and malignant diseases inherently cause lymphopenia, further reduction of lymphocytes with dexamethasone should be avoided if possible and if safe and effective alternative antiemetics are available during the COVID-19 crisis.