Association of COVID-19 with Features of the Peripheral Hemogram Among Cancer Patients Undergoing Chemotherapy

Objectives: Future pandemics involving COVID-19 or other respiratory disorders may pose risks to treatment out-comes among cancer patients on chemotherapy. Here we explored whether diagnosis with COVID-19 might influence how chemotherapy alters the peripheral hemogram of cancer patients. To examine changes in the peripheral hemo-gram before and after chemotherapy depending on whether patients were unexposed to the SARS-CoV-2 virus, had COVID-19, or were recovering from COVID-19. Methods: We retrospectively reviewed the records of 8,900 patients with solid cancers who underwent chemotherapy between October 10, 2022 and March 1, 2023. We compared hemograms before and after chemotherapy within and across the following three groups: 3,215 patients previously unexposed to SARS-CoV-2, 2,771 patients with COVID-19, and 2,817 patients recovering from COVID-19. We compared counts of white blood cells, red blood cells, and platelets as well as percentages of neutrophils between the first blood sampling after admission and the first sampling after conclusion of chemotherapy. Results: Of the various parameters examined, only the changes in counts of white blood cells and platelets differed significantly across the three patient groups. White blood cell count before chemotherapy was lower in patients with COVID-19 than in those unexposed to the virus or those recovering from COVID-19. Platelet count after chemotherapy was lower in patients with COVID-19 than in those recovering from COVID-19. Chemotherapy reduced the red blood cell count and increased the neutrophil percentage in all three patient groups, with the largest changes occurring in patients with COVID-19; however, these changes did not achieve statistical significance. Conclusion: These studies suggest that COVID-19 does not significantly alter the peripheral hemogram of cancer pa-tients who receive effective chemotherapy.