ERBB2 and COVID-19: Additionally, inflammatory cytokines released during severe COVID-19 infection might interact with HER2 signaling pathways, thereby influencing cancer progression and patient prognosis.[11] Immune dysregulation caused by COVID-19 may have a consequential impact on breast cancer, including potential alterations in tumor immune microenvironment and patient prognosis.[12] However, traditional observational studies are biased by unmeasured confounding factors, making it difficult to speculate on the causal relationship between COVID-19 infection and the risk of HER2-positive breast cancer.[13]