Potential biomarkers to evaluate therapeutic response in advanced pancreatic cancer
Most patients with pancreatic cancer are not diagnosed until the disease develops to an advanced stage. It is essential to evaluate tumor response because some patients benefit from a particular therapy, while others do not. Evaluating therapeutic response is crucial to achieve the maximum possible benefit. However, the current criteria for evaluating tumor response requires at least two months after the initial treatment, and by that time, some patients have progressed to an untreatable stage. Thus, robust early response biomarkers, or predictive markers, are required to personalize treatment. In this review, we summarize the novel potential biomarkers for the evaluation of therapeutic response in advanced pancreatic cancer. The biomarkers are categorized into seven groups: serum tumor biomarkers, inflammation markers, circulating tumor cells (CTC) and DNA, non-coding RNA, exosomes, DNA methylation, and other markers. These markers may serve as potential criteria to use in the evaluation of treatment response. Advances in the understanding of the molecular events in tumorigenesis and proliferation have identified potential biomarkers that could be used to evaluate therapeutic responses. A major obstacle, however, is integrating these markers into a system, such as a scoring system, which would be more powerful than evaluating with a single biomarker.