Response assessment in pancreatic ductal adenocarcinoma: role of imaging.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive gastrointestinal (GI) malignancy with poor 5-year survival rate. Advances in surgical techniques and introduction of novel combination chemotherapy and radiation therapy regimens have necessitated the need for biomarkers for assessment of treatment response. Conventional imaging methods such as RECIST have been used for response evaluation in clinical trials particularly in patients with metastatic PDAC. However, the role of these approaches for assessing response to loco-regional and systemic therapies is limited due to complex morphological and histological nature of PDAC. Determination of tumor resectability after neoadjuvant therapy remains a challenge. This review article provides an overview of the challenges and limitations of response assessment in PDAC and reviews the current evidence for the utility of novel morphological and functional imaging tools in this disease.