Background: In recent years, immune checkpoint inhibitors have been used with great success in the treatment of various cancers. However, when used in monotherapy, immune checkpoint inhibitors have a poor effect on pancreatic cancer. This study assessed the efficacy and safety of the use of immune checkpoint inhibitors for the treatment of advanced pancreatic cancer.
Patients and methods: We evaluated patients with advanced pancreatic cancer who were treated with PD-1/PD-L1 inhibitors from 2015-2017. All the patients received PD-1/PD-L1 inhibitors as a monotherapy or in combination with other treatments, such as chemotherapy, targeted therapy, and CTLA-4 inhibitors at the recommended dosages.
Results: For the 43 patients enrolled, the objective response rate was 10.5%, the disease control rate was 50%, the median progression-free survival was 2.3 months, and the median overall survival (mOS) was 5.1 months. The mOS was longer for patients receiving combined therapy than for those receiving PD-1/PD-L1 inhibitor monotherapy (5.4 vs 2.0 months, P = 0.020). Patients receiving immune therapy as a first-line treatment had prolonged survival compared with those receiving it as a second-line or multiple-line treatment, but the difference was not statistically significant (mOS: 7.0 vs 5.1 vs 2.8 months, P = 0.161). There was a reduction in the serum level of CA19-9 associated with the response to treatment. Adverse events were tolerable and were mainly grade 1 and 2. The immune-related adverse events that occurred were hypothyroidism, diarrhea, and rash.
Conclusion: Immune checkpoint inhibitors showed a certain efficacy in the treatment of advanced pancreatic cancer and could confer long-term survival benefits. Combined therapy was more effective and may serve as an alternative option. Further studies should be performed.
Keywords: checkpoint inhibitor; immune therapy; pancreatic cancer.