CD8A and rectal cancer: For example, El et al[11] calculated the immune score by evaluating the average density of CD3+ and CD8+ T cells in pretreatment biopsy samples of rectal cancer, and found that patients with high immune scores in pretreatment biopsy samples had better efficacy of neoadjuvant therapy; Liang et al[3] classified the TSR in pretreatment biopsy specimens of rectal cancer into 3 or 2 categories based on artificial intelligence semi-automatic methods.