Determining the minimal necessary flow cytometry markers to identify prognostic TEMRA cell population in head and neck squamous cell carcinoma 3971

Description Approximately half of patients diagnosed with head and neck squamous cell carcinoma (HNSCC) will experience disease recurrence within one year of initial treatment. Currently, there are few validated factors to predict which patients will experience disease recurrence. In our surgically treated HNSCC cohort, we have identified a subpopulation of T cells that are associated with early disease recurrence when present in high levels in peripheral circulation. We describe these cells as being highly differentiated CD8+ T effector memory cells (CD8+ HD TEMRA), and they are identified via flow cytometry as CD3+ CD45RA+ CCR7- CD27- CD28- CD57+. In order to improve the clinical utility of identifying these HD TEMRA cells as a potential biomarker in HNSCC, we identified the minimal necessary markers to effectively select for these cells while maintaining prognostic significance in predicting HNSCC recurrence. Gating based on live CD8+ CD28- CD57+ cells was sufficient to predict disease recurrence in our HNSCC cohort using a cutoff of > 38% HD TEMRA cells (p = 0.0343, odds ratio = 4.44). In oral cancer cases alone, gating on live CD8+ CD57+ cells was sufficient to predict disease recurrence with a cutoff of > 41.2% HD TEMRA cells (p = 0.0102, odds ratio = 8.21). These gating strategies represent a clinically relevant prognostic biomarker, easily performed on a clinical flow cytometer from a patient blood sample.