Analysis of treatment response with proteins related to tumor immunity in postoperative irradiated cervical cancer patients

Abstract

Abstract We evaluated the relationship between programmed cell death-ligand 1 (PD-L1) and prognosis in patients treated with postoperative radiation for cervical cancer and the impact of neoadjuvant chemotherapy (NAC) on this relationship. Immunohistochemical analysis was performed on biopsy specimens from 42 patients who did not receive NAC and from paired samples before (biopsies) and after (resected tissues) chemotherapy from 46 patients who received NAC to determine the association of PD-L1 with radiotherapy outcomes. In the non-NAC group, patients with ≥ 10% PD-L1-expressing tumor cells prior to treatment had better recurrence-free survival (RFS) than those with < 10% PD-L1-expressing tumor cells (p = 0.001). In the NAC group, RFS was significantly lower (p = 0.005) in the group with a ≥ 5% reduction of PD-L1 expression in tumor cells after chemotherapy than in those with < 5% reduction. In multivariate analysis, only PD-L1 expression (non-NAC group) and the change in PD-L1 expression (NAC group) were associated with RFS. Our results suggest that low PD-L1 expression in a cervical tumor pretreatment is a risk factor for a poor outcome following postoperative radiotherapy. NAC also induces an immunological shift to reduce PD-L1 levels in tumor cells, which negatively influences treatment outcomes.