Abstract
BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) remains one of the most fatal diseases, with its morbidity and mortality showing an upward trend. The application of monotonous immune checkpoint inhibitor (ICI) in PDAC comes to a disappointing endpoint, despite of its great advancements achieved in cancer treatment. However, a promising efficacy can be obtained on condition that ICIs are used in combination with chemotherapy. CASE: We reported a patient suffering from metastatic PDAC with proficient mismatch repair (pMMR) and low expression of programmed cell death ligand 1 (PD-L1). The patient survived for a remarkably long time and showed favorable tolerance to the combination of FOLFIRINOX+Toripalimab (a novel PD-1 inhibitor) administrated after chemoradiotherapy and targeted therapy. Today, the survival benefits gained from this therapy will continue to have a positive impact on him. CONCLUSION: FOLFIRINOX+Toripalimab potentially serves as a novel therapeutic strategy for PDAC in late stage, with durable benefits and manageable toxicity in patients, which is still required to be validated in further research.