RESUMO
<p><b>OBJECTIVE</b>To investigate the effect of high-intensity focused ultrasound (HIFU) and gemcitabine on xenograft growth in nude mice bearing human pancreatic cancer.</p><p><b>METHODS</b>Nude mouse models bearing subcutaneous human pancreatic cancer cell line PANC-1 xenograft were randomized into 4 groups, including a control group and 3 treatment groups subjected to treatments with HIFU, gemcitabine, or both. After the treatments, the tumor was measured on a weekly basis for 5 weeks, and the tumor growth curve was drawn. The tumor inhibition rate was calculated and the expression of vascular endothelial growth factor (VEGF) in the tumor tissue was examined by immunohistochemistry.</p><p><b>RESULTS</b>The tumor volume showed significant differences between the 3 treatment groups (P<0.01), but all significantly smaller than that in the control group; HIFU combined with gemcitabine resulted in the most obvious reduction in the tumor volume. VEGF expression in the tumor tissue was the lowest in the combined treatment group and the highest in the control group.</p><p><b>CONCLUSION</b>HIFU therapy produces definite therapeutic effect on human pancreatic cancer in the nude mouse model, and its combination with chemotherapy is the optimal treatment modality.</p>