For instance, a study involving 35 patients with recurrent, surgically removable GBM found that those who underwent PD-1 therapy before surgical resection and continued immunotherapy after the operation experienced extended overall survival compared to patients who received PD-1 therapy solely after the surgery.[123] A similar clinical study also noted that certain patients with GBM who received ICIs as adjuvant therapy exhibited improved survival outcomes.[124]. This evidence concerns the gene PDCD1 and glioblastoma.