Adjei Antwi, Stella Konadu

Abstract Importance and Objective Pancreatic cancer can lead to severe stenosis of the portomesenteric venous (PV/SMV) confluence due to extrinsic compression or direct invasion. This can result in venous hypertension associated with post-prandial abdominal pain, gastrointestinal bleeding, and ascites. In patients with unresectable tumors, transhepatic PV/SMV stenting has been reported; however, its safety and efficacy are poorly understood. Design, Setting and Participants All unresectable pancreatic cancer patients referred to Interventional Radiology to undergo palliative transhepatic PV/SMV stenting (2011–2024) were collected. Patient demographics, CT scans, transhepatic venograms, and clinical outcomes were reviewed. Intervention, Main Outcomes and Results In total, 129 patients were included; 92% had pancreatic ductal adenocarcinoma. Tumors were unresectable due to unreconstructable vascular involvement, metastatic disease, or poor performance status. Nearly 81% were symptomatic, while the remaining 24 asymptomatic patients presented with significant venous hypertensive varices and collaterals on imaging. Complete venous occlusion was seen in 39% of patients at the PV, the SMV, or the PV/SMV confluence; 97% of procedures were successful, with 4 technical failures at obtaining distal venous wire access. Adverse events occurred in 4 patients. Radiological follow-up was available in 94% of patients. Post-procedural primary stent patency was 80% at a median follow-up time of 20 months. Follow-up was available in 102 of the 105 symptomatic patients, with 85% reporting an improvement in symptoms. Conclusions and Relevance Palliative transhepatic PV/SMV stenting is a technically feasible and safe procedure in well-selected patients. Symptoms improvement can be seen in most patients. High-volume centers should consider this technique for patients with unresectable tumors who present with symptomatic stenosis or short segment occlusion.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) is an aggressive and lethal malignancy. Surgical resection is the only curative modality combined with neoadjuvant chemotherapy to improve survival. Given the limitations of traditional responses such as cross-sectional imaging (CT/MRI) or tumor markers, carbohydrate antigen 19-9 (CA19-9), the 2023 National Comprehensive Cancer Network guidelines included 18F-fluorodeoxyglucose (FDG)-PET as an adjunct to assess response to neoadjuvant chemotherapy. There are common misconceptions on the metabolic activity (tumor avidity) in PDAC so we aimed to describe the baseline characteristics and use of FDG-PET in a cohort of treatment-naive patients with PDAC. STUDY DESIGN: A single-center retrospective study was conducted capturing all biopsy-proven, treatment-naive patients with PDAC who underwent either baseline FDG-PET/CT or FDG-PET/MRI imaging between 2008 and 2023. Baseline FDG-PET characteristics were collected, including primary tumors’ maximum standardized uptake value defined as metabolic activity (FDG uptake) of tumor compared with surrounding pancreatic parenchymal background, and the identification of extrapancreatic metastatic disease. RESULTS: We identified 1,095 treatment-naive patients with PDAC who underwent baseline FDG-PET imaging at diagnosis. CA19-9 was elevated in 76% of patients. Overall, 96.3% (1,054) of patients had FDG-avid tumors with a median maximum standardized uptake value of 6.4. FDG-PET also identified suspicious extrapancreatic metastatic lesions in 50% of patients, with a higher proportion (p < 0.001) in PET/MRI (59.9%) vs PET/CT (44.3%). After controlling for CA19-9 elevation, PET/MRI was superior in detection of extrapancreatic lesions compared with PET/CT. CONCLUSIONS: FDG-PET has significant use in PDAC as a baseline imaging modality earlier neoadjuvant therapy given the majority of tumors are FDG-avid. FDG-PET can identify additional extrapancreatic suspicious lesions allowing for optimal initial staging, with PET/MRI having increased sensitivity over PET/CT.