Grimm et al. BMC Cancer 2010, 10:82 http://www.biomedcentral.com/1471-2407/10/82 during carcinogenesis simulating the situation in human cancer. Additionally a further feature of tumor immune escape mechanisms, the FAS/FAS-L “counterattack”, could be shown in the described murine model. Taken together this model simulates several features of immunological escape mechanisms during carcino- genesis and might serve as a model for immunothera- peutic intervention studies. Acknowledgements This work was supported by The Deutsche Bundesstiftung Umwelt (DBU, 16011). The authors thank the assistance of Mrs. Ulrike Faber in the preparation of this manuscript, and Mrs. Andrea Trumpfheller, Mrs. Sabine Mueller, and Mrs. Mariola Dragan for their technical support. Author details 1Department of General Surgery, University of Wuerzburg Hospital, Germany. 2Department of General Surgery, Molecular Oncology and Immunology, University of Wuerzburg Hospital, Germany. 3Department of General Surgery, Leopoldina Hospital, Schweinfurt, Germany. Authors’ contributions MG was responsible for immunohistochemical analysis and drafting of the manuscript. MG and MB participated in the surgical animal procedures and the surveillance of operated mice. JS, JW and EN assisted in surgical animal procedures, performed the RT-PCR experiments and participated in data analysis. DM was involved in establishing microsurgical techniques. CTG and AMWG participated in the design of the study and its coordination. AT was responsible for the interpretation of all data and drafting of the manuscript. All authors read and approved the final manuscript. Competing interests The authors declare that they have no competing interests. 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