Tumor marker response to SARS-CoV-2 infection among patients with cancer

Inflammatory responses from benign conditions can cause non-cancer-related elevations in tumor markers. The severe acute respiratory coronavirus 2 (SARS-CoV-2) induces a distinct viral inflammatory response, resulting in coronavirus disease 2019 (COVID-19). Clinical data suggest carcinoembryonic antigen (CEA), carbohydrate antigen 19-9 (CA 19-9), and cancer antigen 125 (CA 125) levels might rise in patients with COVID-19. However, available data excludes cancer patients, so little is known about the effect of COVID-19 on tumor markers among cancer patients.

We conducted a case series and identified patients with a positive SARS-CoV-2 PCR test, diagnosis of a solid tumor malignancy, and a CEA, CA 19-9, CA 125, or CA 27-29 laboratory test. Cancer patients with documented COVID-19 infection and at least one pre- and two post-infection tumor marker measurements were included. We abstracted the electronic health record for demographics, cancer diagnosis, treatment, evidence of cancer progression, date and severity of COVID-19 infection, and tumor marker values.

Seven patients were identified with a temporary elevation of tumor marker values during the post-COVID-19 period. Elevation in tumor marker occurred within 56 days of COVID-19 infection for all patients. Tumor markers subsequently decreased at the second time point in the post-infectious period among all patients.

We report temporary elevations of cancer tumor markers in the period surrounding COVID-19 infection. To our knowledge this is the first report of this phenomenon in cancer patients and has implications for clinical management and future research.