A review written by Young, MD, Anderson Cancer Center, USA explained the application of PD-1 inhibitor immunotherapy in B-cell lymphoma. (Blood. Online version on November 8, 2017. doi: 10.1182 / blood-2017-07-740993.)
PD-1 immune checkpoint inhibitor treatment has shown significant efficacy in the treatment of advanced tumors including hematological malignancies. This review focuses on the clinical trials of PD-1 / PD-L1 expression and PD-1 inhibitor immunotherapy for B-cell lymphoma. Relapsed and refractory classic Hodgkin lymphoma usually have PD-1 positive tumor infiltrating T cells, 9p24 gene changes and high PD-L expression. In Phase I / II clinical trials, PD-1 inhibitors alone can bring an objective response rate (ORR) of 65% to 87% and continuous disease control. The median duration of remission in a phase II clinical trial was 16 months. In a phase I clinical trial, nivolumab was used to treat relapsed and refractory B-cell non-Hodgkin’s lymphoma including follicular lymphoma (CD4 positive T cells in the tumor usually have a large amount of PD-1 expression) and diffuse large B cell lymphoma Tumors (also express PD-1 and PD-L1 to varying degrees). Primary mediastinal large B-cell lymphoma often has 9p24 changes. In a phase II clinical trial, the ORR of pembrolizumab was 35%, the ORR of pembrolizumab was 0, and the treatment was Richter transformation. The ORR of chronic lymphocytic leukemia is 44%. Marginal zone lymphoma also has PD-1 expression, but mantle cell lymphoma does not. The review also describes the mechanism of PD-1 inhibitor immunotherapy, toxic reactions, predictive markers and combination treatment strategies.