review of literature on clinical pancreatology - The Pancreapedia

KRAS2 gene mutation found in their associated PanIN lesions. Ductal neoplasms <strong>of</strong> thehuman pancreas, as defined by KRAS2 gene mutations, do not appear to arise from acinarcells. Isolated AMD lesions are genetically distinct from those associated with PanINs, andthe latter may represent retrograde extension <strong>of</strong> the neoplastic PanIN cells or less likely areprecursors to PanIN [409].Experimental pancreatic cancerIn an effort to provide useful models for preclinical evaluation <strong>of</strong> new experimentaltherapeutics, it has been developed orthotopic mouse models <strong>of</strong> pancreatic cancer. Theutility <strong>of</strong> these models for pre-clinical testing is dependent upon quantitative, noninvasivemethods for monitoring in vivo tumor progression in real time. Toward this goal, it wasperformed whole-body fluorescence imaging and ultrasound imaging to evaluate and tocompare these noninvasive imaging modalities for assessing tumor burden and tumorprogression in an orthotopic mouse model <strong>of</strong> pancreatic cancer. Now whole-bodyfluorescence imaging and ultrasound imaging in the mice both allowed for the visualizationand measurement <strong>of</strong> orthotopic pancreatic tumor implants in vivo. The imaging sessionswere well-tolerated by the mice and yielded data which correlated well in the quantitativeassessment <strong>of</strong> tumor burden. Whole-body fluorescence and two-dimensional ultrasoundimaging showed a strong correlation for measurement <strong>of</strong> tumor size over a range <strong>of</strong> tumorsizes. The findings suggest a complementary role for fluorescence imaging and ultrasoundimaging in assessing tumor burden and tumor progression in orthotopic mouse models <strong>of</strong>human cancer [410].Early pancreatic cancerTumor cell migration along the periphery <strong>of</strong> blood vessels to remote sites has been termedextravascular migratory metastasis, which is distinct from direct gross tumor infiltration <strong>of</strong>blood vessels and from intravascular dissemination. A case report was presented whereEUS examination was performed with targeted fine-needle aspiration (FNA) <strong>of</strong> previouslyunrecognized perivascular cuffing by computed tomography, which established the presence<strong>of</strong> celiac axis malignant perivascular cuffing in the setting <strong>of</strong> a T1 pancreatic cancer [411].StagingA retrospective study was performed in 87 patients who underwent surgical resection forpancreatic cancer. Preoperative levels <strong>of</strong> tumor markers such as carbohydrate antigen 19-9(CA19-9) and duke pancreatic monoclonal antigen type 2 (DUPAN-2) were estimated andanalyzed in relation to disease-specific survival (DSS). The CA19-9 level did not correlatewith the DUPAN-2 level. Prognosis correlated with CA19-9 levels, and patients with 185U/mL or lower CA19-9 level showed significantly better disease-specific survival thanpatients with 186-U/mL or higher CA19-9 level. Patients with 151-800-U/mL DUPAN-2 levelshowed significantly worse DSS than patients with 801- U/mL or higher DUPAN-2 level, sothe prognosis was reversely related to the DUPAN-2 level. Patients with increased levels <strong>of</strong>both CA19-9 and DUPAN-2 showed significantly worse disease-specific survival than thepatients without elevated levels. The independent predictors <strong>of</strong> poor DSS (hazards ratio, 95% confidence interval) were the following: non-well-differentiated adenocarcinoma, invasion<strong>of</strong> the portal vein, and increased levels <strong>of</strong> both CA19-9 and DUPAN-2 [412].Recent years have brought important developments in preoperative imaging and use <strong>of</strong>laparoscopic staging <strong>of</strong> patients with pancreatic adenocarcinoma. There are few data about