Effect of immunotherapy on the immune microenvironment in advanced recurrent cervical cancer.

• The immune microenvironment is emerging as a determinant of cervical cancer treatment. • The expression of B cells and PD-L1 increased after treatment with PD-1 inhibitors. • B cells may play a role in cervical cancer immunotherapy. This study evaluated the basic immune status of cervical cancer and the influences of immunotherapy on the immune microenvironment, and analyzed the correlation between changes in the immune microenvironment and prognosis. We retrospectively analyzed the treatment status of 8 patients with advanced recurrent cervical cancer treated with PD-1 inhibitors and detected the tumor-infiltrating immune markers (CD3, CD4, CD8, CD20, CD56, CD68, PD-1, and PD-L1) by immunohistochemistry. All patients showed good tolerance during the treatment. Complete response (CR), partial response (PR) and stable disease (SD) was observed in 3, 2, and 3 patients, respectively. Immunohistochemical analysis showed immunotherapy resulted in increased infiltration of T lymphocytes, natural killer cells, and B cells, especially among those who responded well. The expression of B cells in 4 of the 5 patients with clinical benefit was relatively high, and the expression of PD-L1 in these 5 patients showed a combined positive score > 3. PD-L1 expression increased significantly after treatment with PD-1 inhibitors. Second-generation sequencing showed that the tumor mutation burden of two patients with adenocarcinoma was high, and after immunotherapy, one case recurred after cure and the other remained stable. PR was also observed in squamous cell carcinoma patients with dMMR (p.R2165H/c.6494G > A) and PIK3CA (p.E545K(E9)) mutations. The expression of B cells and PD-L1 has certain predictive effect for the efficacy of immunotherapy in cervical cancer under the condition of high or low T cell infiltration, and can inform treatment decision-making for patients with advanced cervical cancer. [ABSTRACT FROM AUTHOR]