Abstract
Immunotherapy has demonstrated significant potential in the treatment of cancer and is now recommended as a first-line therapy for small cell lung cancer and melanoma. However, a novel response pattern has been delineated, characterized by an abrupt acceleration of tumor growth subsequent to immunotherapy. These unforeseen adverse events are denoted as hyper progressive disease (HPD). The occurrence of HPD is observed not only in patients undergoing immunotherapy but also in those receiving chemotherapy, albeit with a comparatively lower frequency within the chemotherapy cohort. In the management of metastatic pancreatic cancer, the combination of chemotherapy and immunotherapy presents a promising therapeutic approach; however, there remains an unresolved question regarding the association between this combination therapy and HPD. Herein, we present a case report of a 59-year-old patient with metastatic pancreatic cancer exhibiting high PD-1/PD-L1 expression identified through next-generation sequencing data, suggesting the potential efficacy of PD-1 immunotherapy. Therefore, we administered serplulimab (a novel anti-PD-1 antibody) in combination with gemcitabine/nab-paclitaxel. The patient initially exhibited a favorable response to the combination therapy of immunotherapy and chemotherapy; however, subsequent tumor enlargement and a significant deterioration in physical condition occurred. To our knowledge, this is the first reported case of HPD in pancreatic cancer with multiple metastases treated using combination therapy. Based on this case, we propose a potential association between combination therapy and HPD in pancreatic cancer.