Abstract: | The aim of this study was to successfully establish an orthotopic murine model using twodifferent human pancreatic adenocarcinoma cell lines and to propose a 3.0 tesla MRIprotocol for noninvasive characterization of this model. SW1990 and MIAPaca-2 tumor cellswere injected into the pancreas of BALB/C nu/nu mice. Tumor growth rateand morphological information were assessed by 3.0 tesla MRI (T1WI, T2WI and DCE-MRI) andimmunohistology. Proliferation of SW1990 was significantly faster than that of MIAPaca-2(P=0.000), but MIAPaca-2 mice had a significantly shorter survival thanSW1990 mice (41 days and 44 days respectively, P=0.027). MRI couldreliably monitor tumor growth in both cell lines: the tumors exhibiting a spherical growthpattern showed a high-intensity signal, and the SW1990 group developed significantlylarger tumors compared with the MIAPaCa-2 group. There were no statistical differencesbetween the two groups in which tumor size was assessed using electronic calipers and anMRI scan (P=0.680). Both tumors showed a slow gradual enhancementpattern. Immunohistochemistry demonstrated tumor tissues showing high expression of Ki-67.This model closely mimics human pancreatic cancer and permits monitoring of tumor growthand morphological information by noninvasive 3.0 tesla MRI studies reducing the number ofmice required. |