Univariate survival analysis according to the frequency of Vγ9Vδ2 T cells. (A-B) Threshold determination of Vγ9Vδ2 T cells among viable lymphocytes is determined using the optimal cut points, performed using the maximally selected log-rank statistics using the maxstat R package. For a given prognostic parameter, maxstat identifies the optimal cut point that best discriminates 2 patient groups (https://cran.r-project.org/web/packages/maxstat/index.html). The threshold of 0.75 % of Vγ9Vδ2 T cells among viable lymphocytes was selected for this study. (C-D) 5-y OS and 5-y RFS (n = 198 and 161, respectively) were estimated using the Kaplan-Meier method and compared between groups using the log-rank test.