PET in Pancreatic Cystic Neoplasm

Pancreatic cystic lesions (PCLs) are often found due to increased usage of cross-sectional imaging. The prevalence of PCLs rises significantly with age. These lesions comprise a diverse group that may occur from benign cyst, premalignant as well as malignant neoplasms, making diagnosis and treatment extremely difficult. Their detailed morphological information is provided by conventional imaging modalities. But their significant similarities in imaging features often restrict accurate lesions characterization and risk stratification. Positron emission tomography (PET), especially with 18F-fluorodeoxyglucose (18F-FDG), provides functional and metabolic evaluation for cystic lesions. The utilization of FDG differs among cyst subtypes and represents tumor metabolic activity. While mucinous cysts exhibit enhanced uptake in the presence of high-grade dysplasia or invasive carcinoma, benign lesions such as serous cyst adenomas typically show minimal uptake. FDG PET/CT shows better specificity, positive predictive value, and overall diagnostic accuracy, especially in uncertain cystic lesions with high-risk morphological characteristics. Therefore, accurate evaluation of localized diseases, distant metastases, and synchronous cancers is made possible by whole-body PET/CT, which has the potential to significantly alter therapy. In addition to FDG, new radiotracers that target tumor neovasculature, somatostatin receptor expression, cellular proliferation, and tumor stroma, respectively, include 68Ga-PSMA, 68Ga-DOTATATE, 18F-fluorothymidine, and 68Ga-FAPI. By integrating enhanced soft-tissue contrast with metabolic data, hybrid PET/MRI significantly improves diagnostic performance. This chapter overall includes the changing role of PET imaging in PCLs and its potential to enhance personalized risk assessment and treatment.