Background: Although human γδ T-cells that express Vγ2Vδ2-bearing T-cell receptor (Vγ2Vδ2 T-cells) have recently received considerable attention in the development of novel cancer immunotherapies, consensus has not yet been reached regarding the physiological relevance of this T-cell subset in the context of cancer immunosurveillance. Clinical trials of adoptive immunotherapy using autologous Vγ2Vδ2 T-cells have been applied to patients with advanced renal cell carcinoma (RCC) and some clinical benefits have been reported. In the present study, we investigated the correlation between the proportion of γδ T-cells in peripheral before surgery in patients with locally advanced RCC and those clinical outcomes.
Patients and methods: Of 41 patients who underwent surgery for RCC, 13 patients had stage III disease without metastasis. These stage III patients were stratified into two groups based on the peripheral γδ T-cell proportion being greater or less than 8.7% before surgery and were followed up for up to 137 months (median 129 months).
Results: Remarkably, an obvious difference was found in the overall survival and cause-specific survival rate between the two groups. In 6 patients with a higher proportion of γδ T-cells, one patient had lung metastasis, but there were no cancer-related deaths. In contrast, 5 out of 7 patients with a lower proportion of γδ T-cells died during the study and 4 out of 7 patients died due to RCC.
Conclusion: An increase in the proportion of peripheral γδ T-cells is a favorable prognostic factor for patients with locally advanced RCC.