Triple-Negative Breast Cancer and the COVID-19 Pandemic: Clinical Management Perspectives and Potential Consequences of Infection

SIMPLE SUMMARY: The Coronavirus disease (COVID-19) pandemic has resulted in challenges to cancer management, exacerbated by limited clinical resources and caution in preventing COVID-19 transmission between patients and healthcare professionals. The neglect of breast cancer (in particular, triple-negative breast cancer (TNBC)) patients during the outbreak could negatively impact their overall survival, as delays in treatment and consultations provide vital time for tumor progression and metastasis. Herein, we review the shifting clinical management of TNBCs during the COVID-19 outbreak. The suggested treatment recommendations can hopefully minimize virus exposure without sacrificing patient care during times when healthcare systems are overburdened. Further, we review published RNA-seq data to assess the theoretical infectability of metastatic TNBCs to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. These analyses highlight the potential of the virus to infect TNBC cells. Given the known increased susceptibility of cancer cells to viral infection, this additional host cell reservoir may make patients with metastatic disease particularly vulnerable to COVID-19 morbidities. ABSTRACT: The COVID-19 pandemic has caused the need for prioritization strategies for breast cancer treatment, where patients with aggressive disease, such as triple-negative breast cancer (TNBC) are a high priority for clinical intervention. In this review, we summarize how COVID-19 has thus far impacted the management of TNBC and highlighted where more information is needed to hone shifting guidelines. Due to the immunocompromised state of most TNBC patients receiving treatment, TNBC management during the pandemic presents challenges beyond the constraints of overburdened healthcare systems. We conducted a literature search of treatment recommendations for both primary and targeted TNBC therapeutic strategies during the COVID-19 outbreak and noted changes to treatment timing and drugs of choice. Further, given that SARS-CoV-2 is a respiratory virus, which has systemic consequences, management of TNBC patients with metastatic versus localized disease has additional considerations during the COVID-19 pandemic. Published dataset gene expression analysis of critical SARS-CoV-2 cell entry proteins in TNBCs suggests that the virus could in theory infect metastasized TNBC cells it contacts. This may have unforeseen consequences in terms of both the dynamics of the resulting acute viral infection and the progression of the chronic metastatic disease. Undoubtedly, the results thus far suggest that more research is required to attain a full understanding of the direct and indirect clinical impacts of COVID-19 on TNBC patients.