evidence: Despite the current lack of concrete, real-world data linking COVID-19 infection to cancer progression, the science supports the association in theory. [...] Some studies have looked at potential biomarkers of this link between COVID-19 infection and worsening cancer progression, even if it was not a primary end point. [...] The common denominator among these studies is the investigators’ call for additional research. Realistically, they write, it may take years to establish a clear association between COVID-19 and cancer progression, but that makes it even more important to focus on research now. It is also important to note that, even if the existing research cannot find a clear association between the two, they do support the need for biomarker testing to help understand this association.