The Role of Endoscopic Ultrasound in Pancreatic Cancer Staging in the Era of Neoadjuvant Therapy and Personalised Medicine

Abstract

Precise staging of pancreatic cancer is crucial for treatment choice. In clinical practice, this includes the TNM staging and determination of tumour resectability, based on a multimodality imaging workup. International guidelines recommend multi-detector computed tomography (CT), with a dedicated pancreatic protocol, as the first-line tool for TNM staging and evaluation of tumour-vessel relationships. In non-metastatic disease upon initial CT assessment, both magnetic resonance imaging and endoscopic ultrasound (EUS) may add relevant information, potentially changing treatment sequence. EUS may have distinct advantages in pancreatic cancer diagnosis and staging when compared with other modalities, being particularly valuable in the determination of portal venous confluence involvement (particularly in small and ill-defined/isoattenuating tumours on CT), in locoregional nodal staging and in the detection of ascites. As we step forward to a more frequent use of neoadjuvant chemotherapy and to personalised medicine, the importance of EUS-guided fine-needle biopsy (EUS-FNB) also increases. The recent availability of third-generation biopsy needles significantly increased the diagnostic yield of EUS-guided tissue acquisition, providing diagnostic cell blocks in approximately 95% of cases with only two dedicated passes and allowing ancillary testing, such as immunohistochemistry and molecular profiling of the tumour. In this article, the authors present an updated perspective of the place of EUS and EUS-FNB in the staging algorithm of pancreatic cancer. Data supporting the increasing role of neoadjuvant therapy and the importance of a patient-tailored treatment selection, based on tumoural subtyping and molecular profiling, are also discussed.