Current staging systems for pancreatic cancer

Accurate pretreatment staging of pancreatic cancer is a crucial initial step in the development of a stage-specific treatment plan, either on- or off-protocol for any patient with pancreatic cancer. Importantly, current American Joint Committee on Cancer staging utilizes the maximal information available; if surgery has been performed, then pathological information from the resected specimen will provide additional information for both T and N staging. If surgery has not been performed, then staging is based on information from available cross-sectional imaging studies. Although American Joint Committee on Cancer staging was modified in the sixth edition to reflect the survival difference between patients with operable/resectable versus nonoperable/unresectable disease, the precise definitions of resectability continue to evolve. It is essential for clinicians of different specialties to understand the definitions of resectability to facilitate optimal patient care and to allow for accurate interpretation of the literature. This review focuses on important aspects of the pretreatment assessment of patients with particular attention to definitions of resectability. Computed tomography has become the optimal imaging modality for pancreatic cancer staging, but other adjunct studies, including endoscopic ultrasound and laparoscopy, may provide additional staging information especially in circumstances where computed tomography technology is limited. In addition, the process of a standardized pathological review is summarized, with emphasis on assessment of the superior mesenteric artery margin and the definitions of R0, R1, and R2. Finally, the prognostic importance of key components of the pathological report such as lymph node status, lymph node ratio, and treatment effect is reviewed.