Elevated proportion of circulating T effector memory cells is associated with early disease recurrence in oral squamous cell carcinoma – a case report 3958

Description Nearly half of oral squamous cell carcinoma (OSCC) patients experience disease recurrence within one year of treatment, with few predictive risk factors. There is a vital need to identify factors mediating early OSCC recurrence. Here we present two patients which exemplify these disparate outcomes and contrast known oral cancer risk factors. A 53-year-old never-smoker with no known risk factors was diagnosed with aggressive stage 4 OSCC. One year after treatment, he was hospitalized with a femur fracture secondary to extensive metastatic disease, after which he had a rapidly fulminant decline and died. In contrast, an 86-year-old with significant smoking history was diagnosed with similar stage 4 OSCC; two years after treatment she has no evidence of recurrence. Given known risk factors, our older patient with significant tobacco exposure was expected to have worse outcomes than a young, otherwise healthy patient. Instead, we found a negative association between disease outcomes and circulating proportion of highly differentiated T effector memory (HD TEMRA) cells; elevated levels of CD8+ HD TEMRA cells is significantly associated with poor disease control. While both patients had similar diseases and treatments, our 53-year-old patient had 42.8% CD8+ HD TEMRA cells vs 0.23% in our 86-year-old patient. We posit an immunologically aged phenotype, particularly a high HD TEMRA cell proportion, raises OSCC recurrence risk due to poor minimal residual disease control after surgery.