SELL and neoplasm: Perioperative immune cell dynamics were comprehensively profiled using mass cytometry.<h4>Results</h4>Unlike conventional CD4<sup>+</sup> and CD8<sup>+</sup> T cell subsets, Th7R (CXCR3<sup>±</sup>CCR4<sup>-</sup>CCR6<sup>+</sup> CD62L<sup>low</sup>CD4<sup>+</sup> T cell), a Th1-like CD4<sup>+</sup> T cell cluster essential for antitumor immunity, consistently decreased in peripheral blood after tumor resection in both groups (p = 0.0016 and p = 0.0033).