Can We Predict the Progression of Premalignant Pancreatic Cystic Tumours to Ductal Adenocarcinoma? A Literature Reviewa New Parenchyma-Sparing Procedures for Deep-Located Hepatic Tumors

Abstract

Introduction: Pancreatic ductal adenocarcinoma (PDAC) is the most prevalent malignant pancreatic tumour and has a poor prognosis despite advances in treatment. Few studies have retrospectively shown how often PDACs arise from cystic precursor lesions and characterised their tumorigenesis pathways. Consequently, optimal management and surveillance strategies for pancreatic cystic tumours are still debated. This literature review aimed to summarise the evidence on precancerous lesions progression to PDAC and to identify the features associated with a higher risk of malignant transformation. Methods: Medline, EMBASE and Cochrane Library databases were comprehensively searched on 1st February 2021 for primary research articles in English pertaining to pancreatic cystic tumours and their malignant transformation. Nine studies were included in the final qualitative synthesis. Results: Four studies discussed pancreatic intraepithelial lesions (PanIN), three discussed mucinous cystic neoplasms (MCN), and five discussed intraductal papillary neoplasms (IPMN) (Table 1). PanINs were found to be the most common precursors lesion, with approximately 80% of PDACs originating from this precursor lesion. While major guidelines suggest radiological features such as size and nodule location to be predictive of malignant transformation, these features often have low specificity and sensitivity (<70%). Conclusion: The lack of high-quality evidence characterising the features of PDAC precursor cystic lesions potentially leads to a subset of patients undergoing surgery unnecessarily. Advancements in molecular techniques will allow the study of cystic lesions at a genetic level, leading to more personalised management strategies. Larger prospective clinical studies incorporating molecular technologies are needed to optimise long-term surveillance strategies. Table 1