Updates on Imaging Assessment of Pancreatic Cancer for Determining Anatomic and Biologic Resectability.

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy. Imaging plays a pivotal role in the diagnosis and management of patients with PDAC, with treatment strategies largely guided by the tumor stage and resectability at initial diagnosis. The pancreatic CT protocol is the preferred first-line imaging modality, while MRI and PET/CT serve as problem-solving tools. In non-metastatic PDAC, anatomical resectability is mainly determined by the extent of tumor-vessel contact and is categorized as resectable, borderline resectable, or locally advanced disease. Although treatment decisions have traditionally relied on anatomical resectability, a growing body of evidence has highlighted the limitations of this approach. Consequently, an expanded concept of resectability that incorporates anatomical, biological, and host-related conditional factors has emerged. Potential biomarkers that reflect tumor biology include carbohydrate antigen 19-9 levels, imaging tumor phenotype, lymph node status, and metabolic activity on PET/CT. Neoadjuvant therapy (NAT) is widely used to treat borderline resectable or locally advanced disease. However, radiological restaging after NAT remains challenging and tends to overestimate vascular invasion, probably because imaging cannot reliably differentiate viable tumors from post-treatment fibrosis. In this context, biological factors may provide incremental value for treatment-response assessment. This review provides an updated overview of imaging techniques, assessments of anatomical resectability, challenges in radiological restaging after NAT, and biological and conditional factors that may enable more refined risk stratification in patients with PDAC.